Before Friday’s game, Celtics assistant coach Armond Hill showed an inspirational video to the team, aimed specifically at young big men Leon Powe and Glen Davis.

No, it wasn’t Rocky or even Hoosiers. It was a film of the Celtics scoring basket after basket with their big men executing great interior passes. The result – the undermanned Celtics outscored the Cleveland Cavaliers 58-22 in the paint and rolled to a stunning 11-point win, 105-94, over the Eastern Conference leaders.

The Celtics didn’t have Kevin Garnett but they did have Leon Powe. The Celtics didn’t have Brian Scalabrine but they did have Glen Davis, at least for 17 minutes before he was ejected for a flagrant Type 2 foul with 9:09 remaining in the third quarter.

But Doc Rivers, who said at the shootaround in the morning that this would be a phenomenal win, had one of his best games of the season as head coach of the defending NBA champions. Just ask Mike Brown, his counterpart on the Cleveland bench.

Brown said the Celtics deserved all the credit for pulling together and pulling off the upset, even if it was on their home parquet.

For his part, Doc Rivers gave credit to Armond Hill for showing the video and his players for taking the lead.

Paul Pierce said Powe (20 points, 11 rebounds) and Davis (10 points) showed the depth the Celtics have.

Pierce said Davis’ ejection in the third quarter fired up the Green.

Leon Powe said he knew he was going to have to pick it up when Big Baby was thrown out.

Glen Davis said his foul of Anderson Varejao was a case of being in the wrong place at the wrong time.

LeBron James said, with or without Garnett, the Celtics are a great team.

King James said it’s hard to believe home team has won 15 straight in the series.