The period captured two goals and two fights in the first 20 minutes of play as each team tried to vie for the advantage early on.
The Bruins captain most appropriately started the scoring, blasting a shot from the blueline 11:57 into the game, traffic clogging the slot.The goal came on the power play after Sergei Gonchar was called for hooking down Brad Marchand.
Not long after that, things started to get heated and first Shawn Thornton and Chris Neil dropped the gloves 41 seconds after Chara's goal.
Teammate Adam McQuaid followed shortly after, dancing with Zenon Konopka less than two minutes after the first fight.
But the Senators came back, though it was late in the period. Greening tied it up with 1:20 to go in the period after taking a pass from Filip Kuba. Thomas was facing Kuba, and Greening came crashing through the zone and tapped it in through the slot.
Both teams finished with 12 shots on net, after starting off the period slowly. The Bruins only had one shot on net through the first five minutes.