The Celtics knew they had to overcome the Magic’s pick-and-roll in order to win the series. But after a disastrous Game 5 loss,  they have added a possible suspension, two concussions, and failed perimeter defense to the list.

In a snapshot: Kendrick Perkins was ejected after being whistled for a pair of technical fouls and could be suspended, Glen Davis and Marquis Daniels suffered concussions, and the Magic drained nearly 15 3-pointers.

The Celtics, who were on the verge of sweeping just days ago, are headed back to Boston after dropping two straight to the Magic.

Three things what went wrong (and they went so, so wrong)

Possible suspension for Perk: Kendrick Perkins was whistled for two technical fouls in the first half, resulting in an automatic ejection. The bigger problem is he was called for his seventh T of the postseason, an automatic one-game suspension. However, since the league does review technical fouls, one or both could be rescinded and Perkins could play on Friday night in Game 6.

Magic struck first: The Celtics have maintained the entire postseason that the key to winning on the road is striking first. But by the end of the first quarter, their initial 5-0 lead was a distant memory. The Celtics were outscored 31-22 from that point on, giving up 15 points from behind the arc. All of the Magic starters scored at least three points, while Kevin Garnett did not attempt a single field goal. The Magic fought for their shots, outrebounding the Celtics 12-7, and was more efficient at finding the open man (7-4 assists). The C’s allowed the Magic — and their home crowd — into the game early and were never able to kick them out.

Perimeter D disappears: The C’s knew what they were up against at the start of the series. “Their shooting is what has always given us problems,” said Ray Allen. “Their 3-pointer, we’ve got to take that away from them.” Tony Allen echoed, “Considering they’re a team that shoots a gang of 3′s feeding off of Dwight Howard who’s very dominant in the post, we’re going to have to be ready. No if, ands and no buts.” The Celtics were ready in the first four games, holding the Magic to just 31 percent from 3-point range. But their perimeter defense imploded in Game 5. The Magic scored 39 points from long-range off of 52 percent shooting.

Three things that went right (well, not so bad)

Rondo bounced back: Questions of injuries buzzed around Rajon Rondo following a poor performance in Game 4. But whether it was muscle spasms or just an off night, Rondo was more effective offensively in Game 5. He scored 19 points, 10 more than in the previous game in six less minutes. It wasn’t his finest showing of the playoffs, but it showed he is back on the right track.

Robinson was reliable: Doc Rivers has said Nate Robinson will win the Celtics a playoff game. Robinson didn’t pull off the feat, but he was effective. With Rondo in foul trouble and Tony Allen benched for most of the game with a twisted ankle, Rivers turned to Robinson in the second half. He defended the point well, scored five points in six minutes, and even blocked Dwight Howard’s shot.

Celtics are going home: The Celtics didn’t want to have to play a Game 6 in Boston (they didn’t want to play a Game 5 in Orlando in the first place), but they are returning to their homecourt as they look to finish things up. The C’s are 6-2 at TD Garden during the postseason. Records aside, they have to take advantage of the energy the Celtics home crowd is sure to provide on Friday night.