Kyrie Irving has been out of action for the Boston Celtics since he picked up a left knee injury on March 11 against the Indiana Pacers, and while there is a concern that he could miss the rest of the season, it's not something which Celtics head coach Brad Stevens is worried about.

Irving played just 16 minutes against the Pacers earlier this month before leaving due to a sore left knee. He had been dealing with knee soreness at various points in the season, and the Celtics did not initially believe the latest issue to be serious. Now, however, it seems things have changed, as his knee has failed to get better.

According to Boston.com, the point guard will now seek a second opinion on his knee injury, but the fact he has missed a couple of games now with no real timetable of return could be a cause of concern for the Celtics, as it could seriously damage their hopes of going far in the playoffs and chasing a championship later this year.

However, despite the worry that Irving's season is now over, Stevens has said he has not thought about that possibility, adding that the 25-year-old could return at any point.

The Celtics head coach said: “I don’t really think about it until I’m told something like that. I think, at the end of the day, if he doesn’t go on the trip and we know he’s going to be gone for four games, then we have to prepare for those four games regardless.”

Stevens felt it was important to reiterate that Irving isn't just out at the moment in order to rest for the postseason, as he said: “This is not one of those situations where we’re choosing to rest somebody. He’s out because he has a sore knee.” Overall, he is encouraged by the big picture of the situation, so he strongly believes Irving will be back this year.

Irving has been fantastic for the Celtics over 60 games so far this season despite the injury that has been with him since he arrived via trade over the summer to Boston. He leads the team in average points and assists per game, averaging 24.4 points, 3.8 rebounds, and 5.1 assists per game.

He'll be a huge loss for the Celtics in the playoffs if he is unable to continue this season due to his knee, and with Irving seeking a second opinion on his injury soon, it sounds like we might not have to wait much longer to find out if he will step on the court for the Eastern Conference side again this season.

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