Defenseman Kris Letang picked the perfect time to score his first playoff goal, blasting a screamer from near the blue line that ricocheted off Washington goaltender Simeon Varlamov and into the net at 11:23 of the extra period.
Letang had been a doubt to even start the game after suffering a left shoulder sprain in Game Two.
The Penguins were on the verge of sealing the victory in regulation time before the Caps' Nicklas Backstrom scored a power-play goal to tie the game at 2-2 with just under two minutes remaining.
Capitals winger Alex Ovechkin opened the scoring at 1:23 of the first period before Ruslan Fedotenko equalised at 9:29 in the second.
Evgeni Malkin, scoreless through the first two games of the series and overshadowed by the duel between Ovechkin and Sidney Crosby, put the Pens back in front with a snap shot at 15:01 in the third before Backstrom sent the game into overtime.
Capitals' netminder Varlamov finished with 39 saves.










