LOS ANGELES -- Former Boise State quarterback Kellen Moore struggled in his second start of the preseason for the Dallas Cowboys on Saturday night.

Moore completed 8-of-17 pass attempts for 69 yards in the Cowboys, 13-10, loss to the Los Angeles Rams at the L.A. Coliseum. Moore, who was making only his second career start in a preseason game, played the entire first half before giving way to rookie quarterback Cooper Rush.

The Cowboys failed to pick up a single first down on their first three offensive possessions with Moore at quarterback. Overall, they went three-and-out on four of six drives with Moore running the offense; a lack of performance that drew scrutiny from many in the national media.

His best series came early in the second quarter. Moore completed 3-of-6 passes for 34 yards on a drive that resulted in a 32-yard field goal from Dan Bailey. They were the only points of the first half for the Cowboys, who went into the locker room trailing, 7-3.

Rush started the second half strong. On the second series of the third quarter, he led the Cowboys on a 6-play 82-yard drive that ended with the Cowboys' only touchdown of the game. Rush hit tight end Rico Gathers for a 25-yard score, the same player that Moore completed a touchdown to last week.

Rush finished the night 9-of-11 for 104 yards and a touchdown. Fourteenth-year NFL veteran Luke McCown also saw action later in the game. The late offseason free-agent acquisition went 6-of-13 for 31 yards.

A number of Dallas starters did not play on Saturday, including quarterback Dak Prescott, left tackle Tyron Smith, wide receiver Dez Bryant and running back Ezekiel Elliot, who was suspended for the first six games of the regular season by the NFL on Friday.

Moore and the Cowboys will host the Indianapolis Colts next Saturday at 5:00 p.m. MT. The game will air on the NFL Network.