Newcastle striker Michael Owen admits he might have to wait to make his comeback.

The 27-year-old had targetted Sunday's Premiership clash with Chelsea for his return after undergoing the second of two bouts of knee surgery last year.

Manager Glenn Roeder claimed today the England star was "50-50" for the game despite picking up a minor groin strain in training but, if he does not make it this weekend, Owen is confident he will be ready for the game against Reading on Monday week.

Speaking from Newmarket races, he said: "It has been frustrating, but when you play at the highest level, you are open to these big injuries as we play so often.

"The rehab has gone perfectly well. I played in a behind-closed-doors game and everything has gone well.

"We play Chelsea on Sunday, but I am just feeling the effects of doing so much work and I have got a bit of a tight groin at the minute. I am looking at the game after that to be making my return."

Despite Owen's pessimism, Roeder has not yet made his decision.

He said: "At this stage, I have not even discussed it with Michael as to whether he will be back for us on Sunday.

"He is 50-50, but he will not return until in my opinion he is in pristine condition — and he has had a slight groin strain which he picked up in shooting practice at the end of last week.

"His groin is a bit sore, but that is what happens when players have been out for a long time, they pick up niggles in other parts of their body.

"At the moment, we are being very careful with Michael, as we would with any other player.

"He certainly has not been ruled out of the Chelsea game, but if in the end he is, then we will start looking to our next match at Reading."

Owen has spent the last 10 months on the sidelines after rupturing his anterior cruciate ligament during England's World Cup finals clash with Sweden last June.