When you look back at this past playoff series, and perhaps the entire Bruins season as well, one of the key explanations for the first round defeat at the hands of the Ottawa Senators could be attributed to just one word; fatigue. Think back to the end of the regular season, where a team that was desperately trying to avoid another late-season collapse taxed themselves just to get back to the postseason.

Coupled with several veterans who hadn’t skated in a playoff series in two years, several players, Colin Miller, Frank Vatrano, Riley Nash, Tim Schaller, Joe Morrow, Sean Kuraly, Noel Acciari and Charlie McAvoy, getting their first Stanley Cup Playoff experience to go along with an already depleted lineup thanks to the injury bug left the Bruins themselves depleted. It certainly did not help that four of the six games went to overtime, with Game 5 heading to double overtime.

During Game 6, Boston had to weather a bit of an early storm from the Senators, having to go one the penalty-kill three times, all for delay of game. Despite that, and being outshot 12-6 in the opening period, the Bruins held a 1-0 lead, thanks to Drew Stafford’s power-play goal at 18:13.

The second was almost a polar opposite of the first, with the Bruins outshooting Ottawa 12-8 in the period, but it was the Sens that nabbed the lead. After successfully killing Ottawa’s first three man-advantages, Ottawa would finally break through on now-notorious Bruins killer Bobby Ryan’s tip-in on a Derick Brassard shot just 37 seconds after McAvoy was whistled for tripping at 2:46. Kyle Turris gave Ottawa a 2-1 lead at 8:32 with a wrister that beat Rask stick side.

Now down a goal, the Bruins had to regroup after a sloppy middle frame. Boston came out flying to start the third. Just 1:57 in, Patrice Bergeron was able to pick up a rebound off a Brad Marchand shot and stuff home the equalizer.

From there, Boston ferociously tried to prevent the series from seeing yet another overtime, peppering Craig Anderson with shots. The Bruins had several good looks, including a chance by Noel Acciari in front midway through the period and a power-play opportunity when Mike Hoffman was sent off for slashing after snapping Kevan Miller’s stick in half at 13:34. Each time, Anderson stood tall, and despite the Bruins’ best efforts and energy spent on the go-ahead goal, the game headed to sudden-death overtime once again.

As the puck dropped to start OT, it became quite evident that the B’s did not have their legs with them. The extra session started out exactly like the second period, with Bruins miscues and turnover that led to Ottawa firing off the first five shots of overtime. About six minutes in, as Erik Karlsson and Clarke McArthur entered the Bruins zone, David Pastrnak would take what look to be a penalty that could certainly be attributed to fatigue. As McArthur broke into the zone, Pastrnak, trying to keep up, reached and took hold of McArthur’s right arm. Though McArthur may have gone down a bit easy, Pastrnak was called for holding, a play that can directly be associated with tired player desperately trying to prevent a mishap.

The ill-fated penalty would prove costly, as an already-weary penalty-kill unit was unable to stop the Ottawa attack and watched as McArthur picked up a pass from Ryan in front and fire it pas an out-of-position Rask for the series-clincher at 6:30.

Though the Bruins were stocked with veterans who have had their fair share of playoff experience, several first-timers who have played postseason hockey during their minor league careers, a coaching staff that did its best to keep the players fresh – Cassidy would say, after the game, that they used six forwards on the penalty kill in the first – and, yes, they are well-conditioned athletes, the strain either not being in the playoffs the last couple seasons and/or experiencing the Stanley Cup playoffs can wear out even the best sometimes.

Having players in the lineup that have little or no experience beforehand due injuries along with the all extra hockey certainly did not help either. With that, the B’s get an early start on the offseason – albeit not as early as the last two seasons.