Had a beast of a Kihon Session last night

- however as part of it we did some drills and Kihon Combos - Including Mae-Geri - Gyaku-Tsuki (stepping forward with the Mae-Geri).
I found this combo extremely difficult to do at any real speed with any real effect.....

I could do the Combo slowly with form but just couldn't make it work at Kumite speed

Any thoughts about this combo or my problem ?