The Bulls have dominated the top-seeded Celtics through two games in their best-of-seven first round series, largely thanks to Rajon Rondo, who played 40 minutes in Game 2 and put up 11 points, nine rebounds, 14 assists and five steals. As Chicago ran away with a double-digit lead in the fourth quarter, Boston's Avery Bradley even heard Rondo saying the Celtics had given up. 

Heading home for Games 3 and 4, the Bulls had every right to think they've got the Celtics figured out. But on Friday, hours before tip-off, Chicago announced Rondo would be out indefinitely with a thumb fracture suffered in Game 2. Rondo will not require surgery, but ESPN's Chris Haynes reported that the injury is serious and his return is dependent on how far the Bulls make it in these playoffs. Rondo had a cast on at Friday's shootaround and will be reevaluated in seven to 10 days. 

Jerian Grant will start Game 3, with Michael Carter-Williams as his backup. Cameron Payne has been activated and Jimmy Butler is expected to assume a larger role as the primary ball handler on offense as well. The Bulls spent the entire regular season with a question mark at their point guard position. Rondo, who was coming off a season in Sacramento in which he averaged 11.9 points, 6.0 rebounds and 11.7 assists in 72 games, provided sporadic contributions during the regular season, was benched for a stretch and clashed with Butler and Dwyane Wade over the team's direction. 

But a late season revival from Rondo carried into the playoffs, in which he has looked like the point guard that helped pioneer two runs to the NBA Finals with the Celtics, including a championship in 2008. He has been a contributor on the defensive end, and his all around play stabilized the offense and a position on the floor many thought would be a disadvantage for Chicago coming into this series. He was the first Bulls player to rack up 20 assists and seven steals through the first two games of a playoff series since Scottie Pippen in 1990. 

Can the Bulls withstand Rondo's absence and complete the upset in the first round? In his second NBA season, Grant started 28 games for the Bulls and averaged 5.9 points. Carter-Williams played in 45 games and averaged 6.6 points. Payne played in 11 games for the Bulls and averaged 4.9 points in 11 games. There's no one in that group that can replace what Rondo has brought to the floor so far in this series, which means there will be plenty of questions heading into Game 3 as to whether Chicago will fall back to its league-average offensive pace without its starting point guard. 

Before Game 2's victory, Rondo, Butler and Wade -- who viewed themselves as a trio who could compete in the East heading into the season -- had an hour-long meeting after the team's morning shootaround to discuss play calls and strategies. In these playoffs so far, the three have put aside their differences: They're halfway to erasing the memories of a 41-41 season and pulling off a first-round upset as the eighth-seed in the East.

But there's a long road ahead.

Even with home-court advantage and the Celtics having to win four out of five games to win this series, the margin of error has shrunk. Without Rondo, Butler will have to take on an increased role in the offense. Through two games, he has averaged 26.0 points, 8.5 rebounds and 5.5 assists and shooting 40.0 percent from three. Without Rondo, Butler's usage rate on offense should increase. He's also drawn the assignment of guarding Isaiah Thomas for stretches, and will likely need to play close to the full 48 minutes for each game in the remainder of this series. Wade has given Chicago a lift as well, especially in closing stretches in the fourth quarter. Now, his offensive contributions become more paramount with Rondo out of the lineup. 

The Bulls don't need any of Rondo's replacements to replicate his performance in this series so far to advance. They've found a formula that works against the Celtics. They've dominated the paint and the glass so far. They've received contributions from unlikely sources that has propelled an offense that averaged 104.6 points per 100 possessions (21st in the league) during the regular season but is scoring 111.1 points per 100 possessions in the postseason so far. If not Grant or Carter-Williams, the Bulls will need a lift from someone else on offense, unless they expect Butler to carry them for the rest of this series by himself. 

Heading into these playoffs, it was improbable to think the Bulls would take full control of this series after two games in Boston, and even more of a stretch to think losing Rondo would be such a significant loss for the team. After Game 2's victory, Wade talked about the healthy respect for Rondo when the two used to battle as part of the Heat-Celtics rivalry. "That hate is that respect," Wade said. "When we played against Boston back in the day, he knew all the plays. He messes up your first option. And he knows that second option. We were just good enough to have a third option. He was that good." In these playoffs, Rondo has proven he still has something left. In this series, the Bulls have a +14.6 net rating with Rondo on the floor, but are a -5.4 without him. 

But this is still the Bulls' series to win. They'll have to amplify their advantages in this series and the onus is on Butler to carry them into the second round. Without their starting point guard, the Bulls will have to show on Friday that the progress they made in the first two games are still sustainable without Rondo on the floor. They have the pieces to do it, but the door has now opened for the Celtics to get back into this series and avoid a historic upset.