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University of North Texas - Track & Field
     Coaching Staff

Derek Mackel
Assistant Coach

Derek Mackel begins his fourth season as an assistant track & field coach at North Texas after a three-year stint in a similar capacity at the University of New Mexico. Mackel works primarily with the pole vaulters and jumpers.

In the 2013 season, Mackel took the Mean Green to the next level. Junior Shahaf Bareni advanced to the NCAA Championship meet, finishing seventh in the country while also setting a school record.

The 2012 campaign saw a lot of improvement from the women's pole vaulters as sophomore Sarah Vann took home all-conference honors in both the Sun Belt Indoor and Outdoor Championships.

Mackel also coached sophomore Shahaf Bareni to a Sun Belt Outdoor Championship and a North Texas school record in the high jump as well as a new heptathlon record from junior Chelsea Hermes. Bareni would go on to compete in the NCAA West Preliminary Rounds in Austin, Texas.

His first season at North Texas saw two vaulters and a jumper qualify for the NCAA West Preliminary Rounds. Freshman Terrance Williams won second place and a spot on the US Junior Team at the USA Junior Track and Field Championships. Williams would then win another silver at the Junior Pan American games. Christal Brewster and Jordan Wehr were the two pole vaulters to advance to the NCAA West Prelims. Brewster would finish 22nd and Wehr would take 28th.

At New Mexico in 2010, Mackel coached pole vaulter Kyle Walker to All-Mountatin West Conference honors and a spot in the NCAA West Preliminary Round in the pole vault (17'4"). Mackel, also worked with Sandy Fortner, the Mountain West Conference Heptathlon Champion (5723), a qualifier to the NCAA Outdoor Championhips in the Heptathlon. Fortner was named the Mountain West Female Athlete of the Year in 2010. Mackel also coached three women's vaulters in 2010: Kelly Fortner (12'9"), Lauren Jaramillio (12'1") and Amber Menke (12'1"), as well as numerous others.

In 2008, Mackel mentored pole vaulter Robert Caldwell into the 18' club (18'1), and to a 6th place finish at the NCAA Outdoor Championships. Mackel also coached the throwing events at New Mexico and mentored several walk-ons to personal bests in 1 year, including Briana Paxton (158'10 Discus, 45'0" Shot) and Sarah Smartwood (160'10" Hammer).

Mackel, the 2006 NCAA Midwest Regional pole vault champion, also set the Midwest Regional record in that event (18' 1") and was one of the great success stories in UNM track & field history. He began as an unrecruited walk-on in 2002, with a best vault of under 12' in high school. He improved by more than six feet during his collegiate career to become one of the nation's premier vaulters.

He is a 2006 graduate of the University of New Mexico, receiving his bachelor's degree in university studies and received an master's degree in exercise science from the University of New Mexico in 2010.


Stefanie Slekis
Assistant Coach

Stefanie Slekis is in her second year as the North Texas cross country coach and the assistant coach for track and field in 2013.

In just her first two years as the Cross Country coach, Slekis led the Mean Green men's team to their first Conference USA Championship, and the women to a third place finish. Ten North Texas runners received all-conference individual honors. Charlotte Wilson was named to the Conference USA All-Academic team.

At the 2014 NCAA South Central Regional Championships, the men and women's teams continued to surpass their previous rankings, placed within the top ten for the second year in a row, with the men's team finishing 4th and the women's team placing 8th.Charlotte Wilson earned individual all-region honors with her 13th place finish, the highest finish for a female North Texas runner in the past 10 years.Troy Taylor, Alejandro Valencia, and Silvester Harrison earned all-region honors. Troy Taylor placed eighth in the men's 10K race, allowing him to compete in the NCAA Cross-Country National Championships.

In the 2014 Indoor and Outdoor Track and Field seasons, Slekis led the distance program and set seven school records, including: the Men's Indoor Distance Medley Relay, Indoor 5,000m, and Indoor 800m and the Women's Indoor 5,000m, Mile, and Outdoor Women's 3,000m Steeplechase and 10,000m.

The Mean Green distance men recorded six top-eight finishes at the 2014 C-USA Indoor Championships, while the women's side grabbed two runner-up finishes and an additional top-six finish. At the C-USA Outdoor Championships three athletes earned All Conference honors placing in the top three in their events while two additional athletes scored team points in their events with top 8 finishes.

Troy Taylor and Charlotte Wilson went on to represent Mean Green distance at the 2014 NCAA Outdoor Track and Field West Preliminary Round of the National Championship. Taylor competed in the Men's 1500m while Wilson competed in the Women's 3,000m Steeplechase. Wilson also recorded the 5th fastest Women's 3,000m Steeplechase run by any female Australian athlete during 2014 with a time of 10:13.10.

Slekis spent the 2012-13 season as a volunteer assistant coach for Florida State's women's cross country and distance track program. During 2011-12, she served as a graduate assistant coach for the distance group at McNeese State, while completing her master's degree at Arizona State.

In her undergraduate career, she competed for Syracuse University cross-country and track & field teams and she was a three-time Big East all-academic student-athlete, earning the Athletic Director's honor-roll award all eight semesters.

Throughout her collegiate career, Slekis earned All-Big East honors twice as a senior, finishing eighth in the 3000-meters during the indoor season and fourth in the 3000-meter steeplechase in the outdoor season. Stefanie stood eighth in the NCAA East Region in steeplechase (10:20.68) and was a regional qualifier in the 10,000M (34:52.12.)

Her successful career started at Forest Park High School, where she earned 15 all-state honors in cross-country and track.


Elizabeth Allen
Assistant Coach

Elizabeth Allen joined the staff at The University of North Texas as an assistant coach for the men's and women's track and field programs in August 2014. Allen will work primarily with the sprinters and hurdlers as well as assist with administrative duties for the program.

Allen has spent the previous three years at Tennessee State University, where she aided in the development of the sprint, hurdle, pole vault, and combined events program during her tenure. While at TSU, she guided her athletes to 12 Ohio Valley Conference Championship wins, nine runner-up performances, 24 all-conference accolades, five NCAA East Preliminary qualifiers, two USATF junior national qualifiers and a NCAA national qualifier. She coached three different Ohio Valley Conference indoor 55 meter hurdle champions (Arthur Combest, Jason Griffin, and Amber Hughes), two outdoor 400 meter hurdle champions Arthur Combest and Clairwin Dameus), an outdoor 100 meter hurdle champion (Amber Hughes), and an indoor pentathlon/outdoor heptathlon champion (Clairwin Dameus).

Allen also mentored runner-up performances in the 200 meter dash (Amber Hughes), 110 meter hurdles (Arthur Combest), 55 meter hurdles (Clairwin Dameus) and 400m hurdles (Jahleel Michael). Several of her athletes garnered all-conference accolades in sprints (Clairwin Dameus), hurdles (Emanuel Thornton), combined events (Tamarron Key) and earned spots on the 4x100 and 4x400 meter championship relay teams.

The Tennessee State University Tigerbelles won an indoor championship in 2014, and earned a runner-up performance in 2013. Freshman Amber Hughes garnered indoor/outdoor freshman of the year honors; while Clairwin Dameus earned indoor/outdoor athlete of the championship honors by aiding in scoring 54 points in the outdoor championship meet. The women also set the Ohio Valley Conference indoor/outdoor 4x400 meter relay and 4x100 meter relay records in 2014.

Allen began her coaching career as a track and field coach at the University School of Nashville from 2009 to 2011 where she tutored 11 athletes to the Tennessee All-State track and field team. While there, she was a part of the success of state champions in nine events, a USATF Junior National qualifier and a Gatorade Player of the year recipient. Allen also mentored athletes to the re-setting of 13 new school records. A stand-out student athlete, Allen was a four-year member of the Belmont University women's track and field team. She is the record holder in the 100-meter hurdles, 400-meter hurdles, the 4x100m relay and the 4x400m relay. She earned 19 all-conference honors while at Belmont University.

During her career, she was a five-time Atlantic Sun Conference Champion in the 4x100-meter relay, 4x400-meter relay and 400-meter hurdles. In 2006, she competed at the USATF Junior National Meet in the 400-meter hurdles and was a five-time NCAA Regional Meet qualifier in the 4x100-meter relay, 4x400-meter relay and the 400-meter hurdles. In addition, Allen received Academic All-Conference honors three years in a row. Allen graduated from Belmont with a bachelor's degree in exercise science in 2009 before obtaining a master of sport administration in 2011. She currently holds a Level II USATF certifications in sprints, hurdles and relays and is a member of USATF and USTFCCCA associations.

Elizabeth and her husband, Anthony, have a daughter, Lia.


Brendon Kelso
Assistant Coach

Brendon Kelso begins his first year as an assistant track & field coach at North Texas after serving two years as a volunteer assistant coach. Kelso works primarily with the throwers.

During the 2014 season, Kelso helped coach Tom Kalisky qualify for the NCAA West National Championships Preliminary Rounds in the javelin throw with a toss of 210 feet, the third-furthest throw in school history. Heaving the shot out to 48 feet, Deja McKnight grabbed the third-best outdoor shot put mark in school history. In his first year at North Texas, Kelso helped coach Deja McKnight to a second-place finish at the Indoor Sun Belt Conference Championships.

Under his coaching, freshman Victoria Clark launched the fourth-furthest discus throw in school history. McKnight, Clark, and Ngozi Nweke claimed three of the eight scoring places in the shot put, adding 17 points to the women's team score and tying the 200 meter dash for the most points scored in a single event, thus paving the way for the women's team to win the 2013 Women's Sun Belt Conference Outdoor Track & Field Championship.

In that same year, Aaron Sirles broke the school record in the hammer throw and took third place in the shot put at both the Indoor and Outdoor Sun Belt Conference Championships. Sirles capped his senior year with a personal-best discus throw, qualifying him for the NCAA West Prelims. Kelso also helped coach Charleston Lewis to break the school record in the 35 lb weight throw. Solidifying a fourth-place finish in men's weight throw during the Sun Belt Conference Championships, John Garrish posted a personal best and school record of 60 feet and 10.75 inches, surpassing Lewis' mark set earlier that season. Garrish also set the current school record in the hammer throw with a launch of 191 feet and 5 inches, surpassing Sirles' mark set earlier that year.

As a student-athlete at Hardin-Simmons University, Kelso competed in the 2009 DIII National Championships in the javelin throw and holds the school record in the event. He was a four-time American Southwest Conference Champion in multiple throwing events, including the javelin, shot put, and discus, was once named American Southwest Conference Championships Outstanding Field athlete, and twice won the Conference Championships High Point Award.

While earning a bachelor's and master's degree from Hardin-Simmons, Kelso was named the American Southwest Conference Men's Track and Field Distinguished Scholar Athlete three times and was a member of the USTFCCCA DIII Men's All-Academic Track and Field team in 2009.