Paul Pierce had the same number of missed shots yesterday (seven) as points. He had as many turnovers (five) as rebounds. He shot two for nine in a playoff game for a total of seven points. After hitting his first shot, a contested face-up jumper from the wing, he missed seven of his final eight attempts. This was not vintage Pierce, or anything close. If he smelled like roses during Game 2 against Atlanta, yesterday he smelled like a garbage dumpster filled to the brim with nothing but three-years old gallons of milk.

Explaining Pierce’s no-show has to begin with a description of Andre Iguodala’s defense. But it also includes Pierce’s knee, which still bothers him. He wouldn’t admit it, of course, but Doc Rivers told a different story.

“Paul clearly is not 100 percent,” he admitted.

Said Pierce, “The knee was fine. I wore my knee brace today.”

Pierce didn’t actually wear a brace, but the second sentence of his statement was just as truthful as the first. I don’t have any concrete evidence to support my claim (I did spot him clearly limping on his right knee after this play, but since it’s his left knee that’s injured, he probably just banged knees with Hawes), so I’m using circumstantial evidence to defend my point — arguments like “he played 37 minutes and only earned two trips to the free throw line,” and “I know he’s never the most explosive player, but he sure seemed a step slower than normal” and “Pierce has experienced playoff duds in the past, but this one stood out as the worst in my memory.”

(Note: Just for kicks and giggles, here are Pierce’s other single-digit playoff games in the Big Three era:

2008 Game 1 vs. Cleveland: Pierce scored four points on 2-14 shooting in 29 minutes of a 76-72 win, showing no indications that he would drop 41 monstrous points during a Game 7 duel with Lebron James later in the series.

2008 Game 3 vs. Los Angeles: Pierce scored six points on 2-14 shooting in Boston’s initial loss of the ’08 NBA Finals. He responded by averaging 25 points for the last three games of the series.

2009 Game 2 vs. Orlando: Pierce scored just three points, playing just 16 minutes for two reasons: 1) He was in foul trouble the entire first half and picked up his fourth just minutes into the third quarter, and 2) thanks largely to 31 points from Eddie House (!!!!), the Celtics beat the Magic by almost a million (or 112-94).

2010 Game 4 vs. Cleveland, Game 4: Pierce scored nine points on 3-8 shooting in a 97-87 win. This dud was part of a weird series for Pierce. He shot just 34.5 percent and averaged just 13.5 points per game in the series. After the Celtics dispatched Cleveland in six games, Pierce described his play by saying something like, “I had to guard Lebron freaking James. Obviously I didn’t have much energy left for offense.”

That’s it. That’s the whole list.)

The difference between stars and mere mortals: Pierce is confident enough to bounce back from any poor performance. As he said after yesterday’s mess, “I never have doubts.”

But if the knee can’t improve enough to allow Pierce to be Pierce, the Celtics’ chances — both in this series and beyond — will take a major hit.