Despite a strong second-half fightback, the Cheetahs lost 20-17 to Scarlets in their Champions Challenge clash on Friday night in Wales.Scarlets led 10-3 at half-time thanks to a try by Steff Evans and a conversion and penalty from Leigh Halfpenny.The Cheetahs' solitary points in the half came from a penalty by flyhalf Siya Masuku.Scarlets lost Carwyn Tuipulotu to a yellow card just before half-time, and the Cheetahs used their numerical advantage to good effect early in the second half by running in two tries Louis Westhuizen and Daniel Kapepula.Masuku converted both to give the visitors a 17-10 lead.Scarlets, however, hit back with their only try of the half through Johnny McNicholl in the 54th minute.Halfpenny's accurate boot added the conversion to level the scores at 17-all, and the fullback kicked a penalty with 18 minutes to go to secure their 20-17 win.The Cheetahs, who currently lie in 5th spot in Pool B, next face Pau on Sunday, 22 January. Scorers:Scarlets 17 (10)Tries: Steff Evans, Johnny McNichollConversions: Leigh Halfpenny (2)Penalties: Leigh Halfpenny (2)Cheetahs 17 (3)Tries: Louis Westhuizen, Daniel KapepulaConversions: Siya Masuku (2)Penalty: Siya Masuku Teams:Scarlets: 15 Leigh Halfpenny, 14 Johnny McNicholl, 13 Joe Roberts, 12 Jonathan Davies (captain), 11 Steff Evans, 10 Rhys Patchell, 9 Dane Blacker, 8 Carwyn Tuipulotu, 7 Dan Davis, 6 Vaea Fifita, 5 Sam Lousi, 4 Morgan Jones, 3 Javan Sebastian, 2 Ken Owens, 1 Kemsley Mathias,Substitutes: 16 Shaun Evans, 17 Wyn Jones, 18 Sam Wainwright, 19 Jac Price, 20 Tomas Lezana, 21 Gareth Davies, 22 Sam Costelow, 23 Ioan NicholasCheetahs: 15 Andell Loubser, 14 Daniel Kapepula, 13 David Brits, 12 Reinhardt Fortuin, 11 Munier Hartzenberg, 10 Siya Masuku, 9 Rewan