BOSTON (CBS) – Rajon Rondo needs to smarten up.

The Celtics point guard is likely facing a one-game ban for his bump on referee Marc Davis in Boston’s 83-74 Game 1 loss to the Hawks in Atlanta Sunday night, making it much more difficult for his team to get out of an early 1-0 series hole.

With just 41 seconds left to play, and a double-digit deficit down to just four, Celtics forward Brandon Bass and Atlanta’s Josh Smith hit the floor for a loose ball. Rondo lost his cool when Davis whistled the ball dead and called a foul against Bass. He was given a technical –which Rondo said he deserved – but it was the little bump that followed that has the guard in hot water.

“Obviously I was upset about the call and I said some words to Marc,” Rondo said after the game. “I deserved the first tech and, as I was walking, I thought he stopped. My momentum carried me into him — I even think I tripped on his foot. I didn’t intentionally chest-bump him. But that’s what it appears to be.”

NBA rules state that “any player or coach guilty of intentional physical contact with an official shall automatically be suspended without pay for one game.” Rondo was already suspended two games earlier this season for throwing a ball at an official, and the league offices will have that in the back of their minds when they hand down this newest punishment.

What makes the act even more frustrating is that Rondo seemed to be the only member of the C’s that had the motor running from start to finish. He finished the night with 20 points and 11 assists in 43 minutes, shooting 10-for-18 from the floor. While the Celtics still had an up-road battle ahead of them, down four with under a minute left, Rondo’s ejection certainly did not help their comeback attempt and seemed to take the wind out of their sails.

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Now, the Celtics will likely have to deal without Ray Allen and Rondo for Tuesday night’s Game 2. It has the team worried, as they should be.

“I’m always worried, but I would be surprised if that happens,” head coach Doc Rivers said. “I thought Rondo was walking toward Marc, and Marc turned back toward him, and that’s when Rondo bumped him… That’s all it was, in my opinion. But we’ll see.”

“I don’t think [the contact] was done purposely, but that’s up to the league at this point to make a decision,” said Celtics’ captain Paul Pierce. “Hopefully we’ll have him for Game 2. If not, we have guys in this room that are more than capable of stepping in.”

A Rondo absence will force the Celtics to start Avery Bradley to start at the point with Mickael Pietrus likely getting the nod at the two-guard spot (if Allen cannot go once again). Where the Celtics will feel it most will be off the bench, with a heavier burden placed on reserves Keyon Dooling and Sasha Pavlovic.

The knock on Rondo has always been his mental makeup. There is no doubt he can quarterback an offense, but he needs to keep his composure. There is no excuse to lose your cool in the final minute of a playoff game with your team fighting their way back in it.

Hopefully being forced to watch a game from the sidelines will help Rondo smarten up. The Celtics need him — and need him focused — if they want to make a deep postseason run.

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