A week ago the Celtics were run out of Sacramento on the wrong end of a 120-95 score. They went to Denver the next night and lost, as is their custom, on the second night of a back-to-back on the road.

They stood at 23-21 with both the Knicks and Bucks closing fast, and with the trade deadline past there was no way to fundamentally upgrade a team that was hanging by a thread in terms of depth besides the waiver wire. As the week progressed, they lost out on players who signed with better teams (Ronny Turiaf in Miami) young talent in the waiver process (J.J. Hickson) and the biggest target of all in Chris Kaman, who is apparently staying with the Hornets.

The analysts and prognosticators took stock and decided that there was a decent chance they might not even make the playoffs. There’s no use getting angry at the perceived disrespect. It’s math. 

In April, 12 of their 15 games are against teams that are either in the playoffs or competing for a spot. The other three? All on the road in their only back-to-back-to-back of the season. They also have six sets of regular back-to-backs in the final weeks. The schedule is brutal and the depth is thinner than Chris Johnson, another waiver-wire player who went elsewhere.

The Celtics’ fortunes have changed rapidly this season, veering wildly from despair to redemption and back again several times. Haven’t we learned by now that we should never count them out until they’re truly, finally dead?

They beat the Hawks on Monday in a utterly grimy affair, highlighted by a comeback spurred on when Atlanta guard Jeff Teague picked an inopportune time to taunt Ray Allen. Afterward, Kevin Garnett dismissed Teague as a “nobody.” (For all the hand-wringing over Garnett’s supposed rudeness, people will miss his old-school values when he’s gone).

Then on Thursday, the Celtics beat the Bucks -- winners of six straight -- in Milwaukee, 100-91. It was one of their most complete team wins of the season. Paul Pierce scored 25 points and three other starters: Garnett, Brandon Bass and Rajon Rondo, had double-doubles.

The much-maligned bench also had big nights. Mickael Pietrus scored 13 points, Keyon Dooling made all four of his shots and Greg Stiemsma had a fantastic line: six points, four rebounds, three assists, five blocks, four steals and five fouls in 24 minutes.

They’re also about to get some help in 7-footer Ryan Hollins who is expected to sign and be in Philadelphia for Friday’s game with the 76ers that just so happens to be for first place in the Atlantic Division. Hollins isn’t a game-changer, but really no one who was available during the waiver period fits that description.

He’s tall, healthy and can move, and he also carries the Garnett-Pierce seal of approval. On this team, that’s no small consideration.

“Ryan had a chance to workout this summer with Paul and KG,” Danny Ainge said on Thursday’s Big Show. “Ryan was highly recommended by them during the offseason. He was under contract with Cleveland but he was a guy that they respect and a guy they like and they think he would be a good fit with our team.”

Friday’s game at Philadelphia is important. First place in the Atlantic brings with it a four seed and homecourt advantage in the first round of the playoffs. The seventh seed, where the Celtics are currently slotted, brings a first round matchup with the Heat. A Sixer win would also give them the tiebreaker.

It’s important for another reason. These two teams met two weeks ago under similar circumstances and the Sixers wound up blowing the Celtics out to such a degree that Ainge called it, “Probably the most embarrassing game of the season.”

The Celtics are in an interesting phase right now. They’re playing more up-tempo in an attempt to find easier ways to score, but they’re winning games when they muck it up and grind it out. They went up and down the court with the Bucks in the first half on Thursday and scored 56 points. In the second half, things slowed down and they held Milwaukee to just 13 points in the third quarter and 33 for the half.

Somewhere in between this faster pace and their old, reliable halfcourt precision and debilitating defense, is a team that is capable of pulling off a handful of playoff surprises. If -- and it’s a huge if -- they can survive the schedule and get to late April in one piece.

The only thing that’s certain for the Celtics is that there will be more swings of the pendulum between now and then. They will ride the roller coaster between the team that no one wants to play and the one that’s facing the end of the line. Asking for consistency this season is simply asking for too much.

For now, however, on March 23, the Celtics are in an upswing. In the grand scheme of things, a relatively healthy Big Three with a set rotation and a chance to play for first place in the division is about as good as could have been expected. They’re taking it game by game, as Garnett likes to say, and after beating the Bucks that’s not nearly as bad as it was a week ago.