Rooney was sidelined for almost a month due to a nasty leg injury suffered during the home win against Fulham. The England international has made six appearances so far.
Rooney, the fourth highest goal-scorer in United's history, said, the team is the most important thing.
"As long as we keep winning, I'm not concerned. If it comes, it comes. We've got other players who can score goals for us," Rooney said.
Rooney, 26, has enjoyed playing in that position for three consecutive games. The 3-0 win over Newcastle United on Sunday, victory over the Magpies in the Capital One Cup and in the Champions Leage clash with CFR Cluj.
"I was involved in the whole game. I'm not one who won't put the work in and I will do my best for the team. That's all I can do," he said.
Rooney also admitted United's defence was shaky earlier in the season. "We didn't defend well enough in the first few league games, not just the back four but the whole team. But we were brilliant. They are a really big team, a physical team, so we knew we had to defend our box really well. We managed to do that," he said.
In 254 appearances for the Old Trafford club, Rooney has scored 129 Premier League goals.