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Miami remains the prohibitive favorite to come out of the Eastern Conference in the NBA playoffs, but what looked like a coronation a couple days ago has morphed into a dogfight after the injury to Heat big man Chris Bosh.

Bosh, who scored 13 points before suffering a strained lower abdominal muscle shortly before halftime of the Heat's 95-86 win over Indiana in Game 1 of the East semifinals on Sunday, is out indefinitely.

The seven-time All-Star, who averaged 18.4 points and 8.1 rebounds in 2011-12, was expected to handle a number of critical roles against the Pacers' imposing 7-foot-2 center Roy Hibbert.

Miami coach Erik Spoelstra envisioned Bosh's perimeter acumen forcing Indiana's big man away from the basket on defense, opening up lanes to the hoop so the team's two superstars, LeBron James and Dwyane Wade, could drive to the bucket with impunity. Meanwhile, his quickness and top-tier offensive skills also were expected to help get Hibbert into foul trouble.

Both of those plans were coming to fruition during Game 1 before Bosh drove around Hibbert for a jam and strained his ab while extending for the hoop and the harm.

Miami persevered without its top interior presence thanks in large part to the newly minted NBA MVP James, who had 32 points, 15 rebounds and five assists as the Heat grinded out the Game 1 victory,

The contest was deadlocked after three quarters, however, and Indiana was as close as 86-85 when George Hill buried a 3-pointer with five minutes remaining before James took over down the stretch.

With or without Bosh, it was alarming that the Pacers hung around on Miami's home floor despite the fact that Danny Granger, typically Indiana's top offensive threat, was held scoreless in the first half for the first time since April 10, 2007, and finished with just seven points on 1-of-10 field-goal shooting.

"We're not going to change," Pacers forward Davis West said. "We didn't play a good enough game tonight as a group to compete with these guys. We can play a lot better than we did."

That's got to be a scary thought for Spoelstra since he needed the game's best player clicking on all cylinders to dispose of a team that struggled.

Spoelstra wouldn't say who will start in Bosh's place for Monday's Game 2 or how long he expects his big man to sit out.

"We're not even going to speculate," the Miami mentor said. "We just have to see day-to-day. There absolutely isn't a timetable right now. He was in today doing treatment."

Bosh, however, essentially ruled himself out of the semifinals.

"This season has to be extended for me to play again," he said. "So that's what's on my mind. "

James, meanwhile, compared the Heat losing Bosh to Chicago's injury troubles. The top-seeded Bulls, of course, lost both Derrick Rose and Joakim Noah and lost to the No. 8 Philadelphia in the first round.

"It's going to be a challenge for us. We're missing the biggest part of our team, probably the biggest part of our team," stated the MVP. "Nobody feels sorry for the Bulls losing (Derrick Rose) or Joakim Noah getting hurt. Nobody feels sorry for you and we don't want anybody feeling sorry for us. We look forward to the challenge. And we'll be ready."

Ronny Turiaf started the second half of Game 1 after Bosh exited and Spoelstra also could go with shot-blocking specialist Joel Anthony or slide veteran power forward Udonis Haslem over.

Turiaf, who signed with Miami on March 21 after being waived by Denver, plays with energy and offers the opportunity to keep the rest of his rotation intact. Anthony is the best athlete and defensive option, a player who can erase mistakes on the perimeter, while Haslem is probably best-served staying put.

"We feel this team was built with a great deal of versatility. We feel that is one of our best strengths," Spoelstra said. "This will be an opportunity for guys to step forward. But it also will be an opportunity for us to use some of this versatility that we've been talking about."

With James and Wade playing at a high level, the Heat remain the favorites in the East, but losing the other piece of "Miami Thrice" puts Indiana, along with Boston or Philadelphia, back in the conversation.

"It changes their team, but we've got to understand it doesn't allow you to play 5-on-4," Pacers coach Frank Vogel said. "They have got great players they can fill in for him. Obviously, not having to worry about Bosh helps because he's such a terrific player."