Sunderland midfielder David Vaughan has admitted that he will struggle to earn a place in Martin O'Neill's starting line-up.
The 29-year-old underwent a hernia operation after suffering a groin injury just before the Black Cats' pre-season trip to South Korea.
Vaughan returned to action on Tuesday in Sunderland's 2-2 draw with Newcastle United in the Premier Under-21 League game, and played the full 90 minutes.
However, the Wales international fears that it will take him a while to resume playing regularly for the first team.
"Pre-season was very frustrating for me," Vaughan told The Sunderland Echo.
"I finished the season with the injury and, for one reason or another, it didn't get sorted during the summer break. It was tough to have the operation at that time, but I've just got to get back into it now.
"It is tough when you miss pre-season. You come back and the rest of the players are much further ahead fitness-wise.
"You're playing catch-up the whole time so you know it's going to be a couple of months down the line before you're at the same level.
"But the season is halfway through by then. Players are playing for their place during pre-season as well and putting ideas in the manager's head. You miss that opportunity which can be frustrating.
"There's obviously quite a few central midfielders at the club and we've all got different attributes. But hopefully I can get a chance and hold my place in the team."