By Matt Kalman, CBS Boston

Zach Hyman and Auston Matthews crisscrossed just inside the Bruins’ blue line with Hyman carrying the puck, and the Toronto top-line forwards might’ve salivated had they not been so focused on getting to the Boston net early in the first period Saturday at TD Garden.

READ MORE: Worcester Remembers 6 Firefighters Killed 22 Years Ago In Cold Storage Fire

Despite a television timeout less than half a minute earlier, Matthews, Hyman and Connor Brown were on the ice against the Bruins defense pair of Adam McQuaid and Torey Krug instead of Zdeno Chara and Charlie McAvoy.

A blown read by McQuaid, a pass to Matthews in stride for a wraparound attempt and a Brown bat-in of a rebound gave the Maple Leafs a 1-0 lead on their way to a 4-3 win in Game 5 of the Eastern Conference first round, and ended Bruins coach Bruce Cassidy’s honeymoon.

Cassidy had barely been criticized for his decisions since taking over as interim coach in February 2017 and taking the full-time job last summer; rightfully so. He’s been on target with almost everything he’s done.

He’s not above reproach, however, and a couple of his mistakes were part of an overall disappointing night by the Bruins in all aspects of the game. Now they’ll have to go to Toronto for Game 6 again looking to close out this series and advance to face Tampa Bay.

Toronto coach Mike Babcock scored some early points for his line juggling in the face of Nazem Kadri’s return to the lineup from suspension and Tomas Plekanec’s rise from the dead. Even after the Maple Leafs’ warmup, Babcock made a tweak to put Plekanec between Patrick Marleau and Mitch Marner, and have Kadri center William Nylander, who’s usually on the first line, and rookie Andreas Johansson.

From the outset, Cassidy seemed to be more concerned with the Kadri/Nylander combo than the Matthews trio, which had been shut down by Chara/McAvoy the whole series. Matthews soon took advantage of the advantageous change by Cassidy, and Kadri and Johansson later took advantage of a misplay by McAvoy to make the score 2-0.

“Four balanced lines, you know obviously … at the end of the day you’ve got to pick your poison when you see that balance,” Cassidy explained. “I’ve said this, I think we’re comfortable with most of the matchups every night. At the end of the day we’ve asked our players to accept the matchup you get and outplay the guy across from you, and a lot of times we do. Tonight, even strength there at the start, we didn’t.”

Whether he truly believes every Bruins defenseman has an equal ability to stop every Toronto forward or Cassidy was just trying to not insult any of his players, the Bruins momentarily lost both the physical and psychological edge they had by having Chara bottle up Matthews. The second-year Toronto center wasn’t just unproductive, he was frustrated through four games, and he returned to his flustered state when Cassidy matched up Chara against him starting later in the period. Matthews finished with one shot on net and late in the third period he fired a shot so hard off the glass on the rush that one had to wonder if there was nine days’ worth of frustration behind the attempt to extend the Maple Leafs’ lead.

It’s on the players to execute the game plan, which Cassidy has been transparent about and sounds like the type of plan that should work (and did work for most of the first three games) to stifle Toronto. But it wasn’t worth overthinking the matchups when one considers how well Chara/McAvoy fared against Matthews earlier in this series and how much sneaky skill Hyman and Brown possess.

READ MORE: Boston Police Warn About Drinks Being Spiked With Drugs At Bars

Down 4-1 after 11:55 had passed in the second period, Cassidy made his boldest move – he pulled Tuukka Rask, the first time Rask has been pulled in the playoffs in his career and the first time since 1995 the Bruins pulled a goaltender in the postseason. Rask had allowed four goals on 13 shots, the straw being James van Riemsdyk’s power-play goal from right at the left post after the Bruins lost a puck battle below the goal line.

“I didn’t think he had it tonight,” Cassidy said of Rask. “So we went with Anton [Khudobin], who’s been very good for us. And then there’s always that part that gets the rest of the team’s attention as well. So it’s both, I don’t want to quantify what percentage was each.”

If Cassidy sensed Rask was off – and singled out Tyler Bozak’s point-blank goal that gave Toronto a 3-1 lead after a Chara/McAvoy breakdown – as an example of Rask’s ineptitude on this night, why didn’t he pull Rask after the Bozak goal? The Bruins needed a spark and eventually got it when Khudobin went in. If the Bozak goal was that bad (it really wasn’t considering he streaked to the net alone after Chara, McAvoy and Patrice Bergeron’s line collectively fell asleep), that was the time to ty to shift the momentum of the game.

The coach has done a lot more positive than negative, from empowering his young players to allowing everyone to play to their strengths and keeping a positive attitude in the face of some severe adversity. He won’t be defined by Game 5 any more than Rask or Chara and any of the Bruins should be defined by it.

Rask had a rough game and he paid the price with a public shaming. Afterwards, he continued with the criticism of his play.

“Probably could’ve stopped more pucks with my eyes closed,” he said.

One can take the Bruins’ 20 shots on net in the third period, 45 shots on net in the game and season-high 90 shot attempts as a positive that they were right there until the end and should be able to carry that over to Game 6. But it took too long for the Bruins to play with the type of anxiety necessary to match the Maple Leafs’ desperation. The offense was frantic and not methodical enough to get Frederik Anderson out of position or uncomfortable in the crease.

The Bruins didn’t know Kadri would get suspended when they strategized for this series. Their plan worked in Game 1 and continued to succeed, even in their Game 3 loss, without Kadri. There’s no reason to do anything different now except throw out memories of Game 5.

Game 6 will provide a great chance for everyone – goalies, skaters and coaches – to reset and get back to the game plan that should lead the Bruins into the next round.

MORE NEWS: Coronavirus In Massachusetts: Today's Developments

Matt Kalman covers the Bruins for and also contributes to and several other media outlets. Follow him on Twitter @MattKalman.