Garnett, who doesn't like contact, is finding out - the same way the Bulls' Carlos Boozer and others have - that trying to move Allen off the low blocks is almost impossible to do. Not that Garnett really wants to mix it up down there unless he has to.
At times Garnett has been very good in this series, but Allen deserves substantial credit for helping to limit Garnett to nine points on 3-for-12 shooting in Game 4.
Allen loves the contact under the boards, but he has also demonstrated an ability to calmly take shots when the clock is running down, something that plenty of veterans would prefer not to do. He and Thaddeus Young seem to have developed a knack for knowing where the other will be when a pinpoint pass is required in the confines of the paint.
Through four conference semifinal games, Allen leads the team in field-goal percentage (15 for 28, 53.6 percent). He's averaging 8.5 points per game, and his 6.5 rebounds per game are second only to the 8.3 rebounds by Evan Turner. Allen leads the team with 10 offensive rebounds.
While his play has surprised fans in these playoffs, none of this is a surprise to Temple coach Fran Dunphy.
That's because Dunphy, Allen's coach for four stellar years at Temple, recognized his star's talents soon after plucking him out of Pennsbury High School in Bucks County.
"I think he has a great feel for the game and his knowledge of basketball is outstanding. He was very well- coached in high school and he just had a great sense of where to be on the court," Dunphy said. "He was also extremely unselfish. He never thought about just himself on the court but always about others. I think he's just got an extraordinary feel for the game on offense and in particular on defense."
Selected with the 50th overall pick in the 2011 draft, Allen, 23, has stepped into the Sixers rotation with the same ease that he did when he left Pennsbury and moved into the Owls lineup. The four-year starter left Temple as the school's all-time leading rebounder.
While much of his success is probably attributable to four solid years of college ball, the player who Dunphy said "might be the smartest player" he has ever coached admitted "at first it was difficult."
"When I first started getting minutes with the team I went out there with a lot of nerves. But after a while I started to calm down and my confidence started to come around. After a while I didn't really worry about it and I started playing with confidence," said Allen, who started 15 times in the regular season.
Collins gave the Sixers off Saturday. Allen and his teammates didn't need a practice to know what must be done if the Sixers are to be successful in Game 5 and win in Boston for the second time in this series. While they staged a huge rally Friday, falling behind 14-0 at the start almost buried them in a 3-1 hole.
"We can't let Paul Pierce, Garnett, and [Rajon] Rondo and those guys get off early and start to get hot," Allen said. "In the two games they won, Garnett had it going early. We know that we can't let that happen. We've got to cover them and make it tough for them to score, and we have to continue to rebound and push the ball."
Contact staff writer John N. Mitchell at email@example.com. Follow him on Twitter @JmitchInquirer.