Chelsea's draw with Arsenal handed Manchester United the Premiership title for the first time since 2003.
The dismissal of Boulahrouz (r) proved costly for Chelsea
Champions for the previous two years, Chelsea found themselves a man and a goal down after Khalid Boulahrouz was sent off for fouling Julio Baptista.
Gilberto Silva put away the penalty as keeper Petr Cech went the wrong way.
Chelsea mounted a spirited rearguard action after the break and with 20 minutes left Michael Essien pulled them level with a courageous diving header.
Chelsea did not relinquish their title easily - their second-half performance was nothing short of remarkable - but they badly missed Didier Drogba, who was ruled out of the game with an ankle injury.
Salomon Kalou stood in for Drogba, but the former Feyenoord striker struggled to hold the ball and allow Chelsea's midfielders to come into the game.
This was the first time these two sides had met since Chelsea's Carling Cup final win, a match that had ended with a mass brawl.
Sunday's game also proved something of a scrap, though more in the sense of some protracted periods of disjointed play than of the players squaring up to one another.
With the game disrupted by a spate of free-kicks it took nearly near 35 minutes before a goalkeeper had to make a save, Cech comfortably holding an effort from Arsenal striker Emmanuel Adebayor.
Two minutes before the break Boulahrouz's dismissal left Chelsea in all sorts of problems.
It was the first time Boulahrouz had played for Chelsea since 17 March and his lack of match practice was evident as he allowed Baptista to nip ahead of him.
Boulahrouz compounded his error by scything down the Brazilian from behind, in the process earning himself a red card.
Cech had no success in saving any of Liverpool's penalties in the Champions League semi-final shootout and the Czech goalkeeper proved similarly incapable of stopping Gilberto's spotkick.
In the second half, Arsenal failed to capitalise on their numerical supremacy and, after William Gallas missed a good chance, Essien's flying header revived Chelsea's hopes of securing a miraculous win.
Shaun Wright-Phillips had flitted in and out of the game up to this point, but he dramatically flitted in when he sent over a cross to the near post that was flicked past Jens Lehmann by Essien.
Soon afterwards the former Lyon midfielder volleyed over the bar following a corner, while Frank Lampard forced a good save from Lehmann.
In stoppage time Kalou's shot was somehow tipped over the bar by Lehmann, while Emmanuel Eboue thrashed an effort against the crossbar.
Arsenal manager Arsene Wenger:
"We wanted to win the game and leading 1-0 with our 11 men against their 10 men we could have.
"That's where we have shown we were too easy and we were punished for it.
"We're still a bit too young to keep our focus, but credit to Chelsea for fighting to the last minute - that is why football is so great."
Chelsea manager Jose Mourinho:
"This was a game to remember and showed how big Chelsea are as a club.
"I'm very proud of my players. Normally when a team has a lot of success and loses a championship it's lack of motivation, not the same spirit or ambition, but it was exactly the opposite.
"My team was brilliant."
Arsenal: Lehmann, Eboue, Gallas, Toure, Clichy, Diaby (Hoyte 79), Fabregas, Silva, Denilson (Hleb 59), Adebayor, Julio Baptista.
Subs Not Used: Almunia, Senderos, Djourou.
Goals: Silva 43 pen.
Chelsea: Cech, Ferreira, Boulahrouz, Terry, Bridge, Mikel (Diarra 74), Essien, Lampard, Wright-Phillips (Sinclair 80), Joe Cole, Kalou.
Subs Not Used: Cudicini, Makelele, Sahar.
Sent Off: Boulahrouz (43).
Booked: Mikel, Essien.
Goals: Essien 70.
Ref: A Wiley (Staffordshire).