BOSTON – Nothing went right for the Boston Bruins in Monday afternoon’s desultory 4-0 loss to the Colorado Avalanche. It was their own fault, coach included, as Bruce Cassidy was quick to point out afterward.  It was bad enough that breakdowns allowed Colorado to jump out to a 2-0 lead in the first period, but then Tuukka Rask made a colossal misjudgment on the Avs’ third goal in the third period and that was that.

Here are three thoughts from the game:

THE COACH

Attempting to deflect blame away from the players is right out of the coaches’ handbook. “We’ve got to coach better,’’ is one of Bill Belichick’s go-to lines after a loss. It may be a relatively minor point but all the same I like the way Cassidy included himself among those who fell short on Monday. “The core group that we rely on – it just wasn’t a good effort from young, old, in between. And clearly put myself in that category,’’ he said. I like a coach who will take a share of the heat when his team doesn’t measure up. And it’s probably something that won’t go unnoticed in the Bruins’ room.

THE ROOKIES

Yeah, I know plus-minus is just one stat among many and it’s been discredited a bit, but there’s no sugarcoating the fact that both Anders Bjork and Jake DeBrusk finished with a minus-3 and Charlie McAvoy with minus-2. Not good. What is at least a little encouraging is that the players owned up and said the right things. “It’s a game I want to forget – but use as a learning experience,’’ said DeBrusk, who played 13:00, down from 14:05 in Game 1. “They’re giving us chances. We definitely have to take advantage of them and learn from our mistakes,’’ added Bjork, who played 14:38 after logging 16:14 on opening night. McAvoy went from 22:00 in Game 1 to 19:28. Remember, there are going to be days, and nights, like this for the rookies. Now we see how they respond. “I think they are good bounce-back guys. They are high character, and they’ll keep coming. But tonight it just didn’t work out,’’ said Cassidy.

THE LINES

Cassidy, missing injured centers Patrice Bergeron and Noel Acciari, didn’t hesitate to mix things up when his team struggled. Bjork and DeBrusk started the day on a line with David Krejci. By the end,  Bjork was with Sean Kuraly and Ryan Spooner, while DeBrusk was with Riley Nash and Tim Schaller. Too soon? Nope. It was worth a try on a day when the Bruins spun their wheels. “I never found the right combination. So I think it goes on the players – it’s their job to play, whatever position – and it’s up to the coach to find the chemistry. I couldn’t find it, so shame on me,’’ said Cassidy.