With World Cup Qualifying tomorrow, both teams will be missing some key players. Houston will be without two defenders: Hainault and Taylor a midfielders: Garcia and regular contributor: Watson. Hainault is the most important of those players as he's been a starting central defender for them all season. Garcia is relatively new to the team and hasn't fully cemented himself into the squad yet.
Meanwhile on the other side of the ball, Salt Lake will be without midfield lynch pin Kyle Beckerman, top forward Alvaro Saborio, and the team's second best midfielder in Will Johnson. Wide back Chris Wingert is suspended for the match. Perhaps, more importantly 2010 MLS defender of the year Jamison Olave is doubtful to play. RSL's record with / without Olave is night and day. In 2012, RSL's regular season record with defender Jamison Olave starting is (W-L-T): 11-4-1. Without Olave in the lineup: 3-6-3. On the road and without Olave, RSL's record is: 0-3-2. Olave hasn't appeared in a MLS game since a July 21 and isn't expected to play tonight either.
Furthermore, Real Salt Lake have an abysmal record in the Lonestar State. RSL have never won in Houston (0-7-1 all time) and furthermore have never won in the state of Texas. RSL's combined road record against both Dallas and Houston is 0-17-3. Yes, that's 17 losses and 3 draws since the inception of their franchise back in 2006.
In addition to that, Houston opened a new stadium earlier this year and has yet to lose a game in it. Houston is one of two MLS teams still undefeated at home in 2012 with 8 wins and 5 draws and a goal differential of 14.
Current odds see Houston as a favorite in the -120 range. That line should be in the -150 range given lineup absences, historical performance, and Houston's home dominance.