The Houston Texans are looking to make a run for the Super Bowl this season, but they're entering the season concerned about wide receiver Andre Johnson's health.

Knee and hamstring injuries have limited him to a total of 20 starts over the past two seasons. Johnson turned 31 in July and missed organized team activities and minicamp because of arthroscopic knee surgery. He was 100 percent entering camp but suffered a minor groin injury that kept him out.

In the third preseason game, he came down on the point of the football and had to leave the game for X-rays on his ribs that were negative.

What frustrates the team the most is that Johnson still is outstanding-when he plays. He averaged 19.4 yards on four catches in preseason.

Johnson is still one of the league's top receivers when he's on the field, but his health remains to be the single most important issue for a team hoping to reach their first Super Bowl.

Johnson's injury is a main issue for the Texans, but he's not the only injury going into the start of the season.

INJURY UPDATE: Outside linebacker Whitney Mercilus, who led the team with 3.5 sacks in preseason, will be the team's first first-round pick to not open the season as a starter. Mercilus, who plays on the weak side, had a terrific camp and preseason but will come off the bench in a rotation with Connor Barwin and Brooks Reed.