The Boston Celtics were dealt a huge blow yesterday, as it was announced that Kyrie Irving's knee surgery last month would rule him out for the rest of the regular season, as well as the playoffs.

The Celtics guard underwent knee surgery last month to remove a tension wire that been placed there during a procedure to repair a fractured patella in 2015. He was only expected to miss three to six weeks, but he will now not return to the court until next season.

This is such a big disappointment for Boston, as they've now gone from one of the favourites to make the Eastern Conference Finals to now potentially being knocked out of the postseason in either the first or second round.

Irving reacted to now being sidelined for the rest of the season on his Instagram account, saying how this latest setback in his career will truly test himself as a professional, and how he's still going to be there at the TD Garden during the playoffs backing the Celtics despite not being able to play.

He said: "The hardest thing to do sometimes is accept the uncontrollable things life throws at you. You try consistently to learn, grow, and prepare everyday to equip your mind, body, and spirit with tools to deal with some of those things, but I feel when those moments arise they all give you a sense of unfulfillment, simply because it puts some of your professional journey and goals on a brief hold.

"It's simply a test of your perseverance and Will, to be present, even in the wake of what's going on. In this case, finding out I have an infection in my knee is definitely a moment that I now accept and move past without holding on to the all the what ifs, proving the nay-Sayers completely f***ing wrong, and accomplishing the goals I've set out for the team and myself.

"This season was only a snapshot of what's to come from me. Trust Me. "The journey back to the top of Mt. Everest continues." #StandingRockSiouxTribe

Irving finished by saying: "Let's go Celtics!! Celtics fans, I look forward to hearing how loud it gets in the TD Garden during the playoffs and experiencing how intense the environment gets. Thank you all!"

With Gordon Hayward and Marcus Smart on the sidelines as well, things don't look promising for the Celtics in the postseason. They're certainly going to miss Irving's productivity, as he has averaged 24.4 points, 5.1 assists and 3.8 rebounds on 49.1% shooting in 60 games in his first season in Boston.

The Celtics begin life without Irving this season when they play against the Chicago Bulls this evening.

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