In a surprising announcement that could have serious ramifications on their first-round playoff series, the Chicago Bulls shelved starting point guard Rajon Rondo indefinitely with a right thumb fracture.

Rondo’s resurgence was a vital component of Chicago’s late-season drive to the eighth seed, and he’s a major reason why the Bulls own a 2-0 series lead against his former team in the playoffs, averaging 11.5 points, 10 assists, 8.5 rebounds and 3.5 steals in the two games against the Boston Celtics.

According to the Bulls, Rondo suffered the injury in Tuesday’s commanding Game 2 victory, and X-rays revealed the thumb fracture. The injury will not require surgery, but he will not take the floor for Game 3 on Friday night. Keep in mind, Rondo once finished a playoff series with a hyperextended left elbow, but an injury to a point guard’s shooting hand — even a non-shooting one like Rondo — is of concern.

The Bulls have traditionally started second-year point guard Jerian Grant in Rondo’s absence this season. The team’s other options include Michael Carter-Williams, Cameron Payne and Isaiah Canaan — none of whom inspire as much confidence as a four-time All-Star with championship experience. Payne, a 2015 lottery pick who was acquired from Oklahoma City Thunder for both Taj Gibson and Doug McDermott at the trade deadline, has played sparingly since injuring his foot in late March.

The Bulls were actually better with Grant and without Rondo on the floor during the regular season, but the return of “Playoff Rondo” made Chicago a different team. He orchestrated an offense that picked Boston to pieces, and on the other end, he seemed to know the game plan before it unraveled.

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“When we would play Boston back in the day, Rondo knew all the plays,” Bulls teammate Dwyane Wade said after Rondo finished one rebound shy of a triple-double in Game 2. “He messes up your first option, and then he knows your second option. … He was that good, and I think for myself and Jimmy [Butler] to have someone who’s so locked in, that gives us a different voice … and he’s watching film all the time, so it’s key when you have a point guard like him that controls the whole game.”

Carter-Williams is Chicago’s only other point guard who entered this series with any experience as a playoff contributor, starting six games for the Milwaukee Bucks in a first-round loss in 2014-15. Payne averaged just six minutes on the end of the Thunder’s bench last season, while neither Grant nor Canaan had every appeared in a playoff game. All of which leaves Bulls coach Fred Hoiberg little option beyond Wade or Butler serving as de facto point guards in bigger lineups going forward. But …

With Rondo, the Bulls looked poised to pull off the upset against top-seeded Boston. Without him? Well, we’ll have to find out on Friday night, but Isaiah Thomas is surely excited about the matchup.

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Ben Rohrbach is a contributor for Ball Don’t Lie and Shutdown Corner on Yahoo Sports. Have a tip? Email him at rohrbach_ben@yahoo.com or follow him on Twitter! Follow @brohrbach

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