Pierce wasn't great last night but he wasn't the reason why we lost this game.
Caron Butler, who most here would consider at best a peer of Pierce (in fact, I'd wager that the majority here consider Pierce better) managed to shoot 46% and have his own moments of brilliance when he outshined LeBron. And Butler had to spend just as much energy on the defense end as Pierce...probably more, in fact, since he doesn't have nearly as much defensive help from his teammates as Pierce gets from the other Celtics.
Firstly, Wally Szczerbiak defended Caron Butler for the majority of the series. Give Pierce Wally and you get a bunch of hoops. LeBron was the secondary defender on Butler and defended him on crunch possessions. I think he defended him game six after Butler dropped 32 and the game winner on them in game five, and James shut Butler down in game six.
Secondly, James destroyed Caron Butler on the other end. He murdered Butler and his team. The reason they lost was because the Wizards couldn't slow James down. Likewise with James to Wally, Butler was the secondary defender on James. Unlike the Butler defending James, Butler didn't torch James throughout the series. And no Butler was not spending as much energy on defense as Pierce because he wasn't on him as often as Pierce, that would be Stevenson.
Butler didn't play well for most the series. He shot a respectable percentage but outside of one good game he didn't crack 20 points once. The first two games he scored 14, then 12.
For most of the series Butler shot long jump shots, forced the action, refused to attack Wally or James. That' why his FT attempts are so low. He didn't move well without the ball, he didn't pass the ball well. That's part of the reason why Cleveland's offense had no creativity and low assists throughout, also why their offense was stagnant and easy to defend. Caron's lack of offensive production led to Washington never scoring 100 points, only once scoring above 90.
Butler's offense was better but only marginally and Pierce has been very very poor offensively. Butler's D is a joke, Pierce's D has been all-defensive level. Huge difference.
Pierce is a much better player than Butler and even with his large offensive struggles he's outperformed Butler in the postseason against LeBron James.