The Bruins got some encouraging health news this week as injured B’s defenseman Kevan Miller was able to skate on his own for 15 minutes Sunday at Warrior Ice Arena while the rest of the team was in Pittsburgh.

The 32-year-old Miller has been out all season while trying to return from two different kneecap injuries suffered last season that kept him out of the entire postseason and limited him to just three games since the beginning of March. Miller underwent a procedure to assist in the healing process last month when he underwent a setback while trying to return earlier this season, so Sunday’s twirl was his first chance to get back on the ice and skate.

For a player that hasn’t played in almost a year now like Miller, any news is good news.

“That’s step one,” said Bruce Cassidy. “That’s a positive.”

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Certainly, it’s good news, but it’s also the very beginning of a recovery process that Miller has already experienced setbacks to a couple of times. Given the normal timetable for players just returning to the ice from an injury, it would be at least 7-10 days before Miller would be anywhere close to returning to game action.

The Bruins will have their All-Star break and bye week over the next 10 days, so it would be at least a few weeks before Miller would be ready to return barring the kind of setbacks that have plagued him since suffering the kneecap injuries.

It remains very much an uphill battle for the rugged D-man in the last year of his contract with the Bruins, but he’s also a tough-minded player that the B’s have absolutely missed during last year’s playoff run and this season. Some of the perceived ability to push these Bruins players around on the ice is because they don’t have the hardnosed 6-foot-2, 210-pound Miller out there to protect his teammates.

Given Zdeno Chara’s age and Charlie McAvoy’s inconsistency this season, Brandon Carlo has ably carried a very heavy load for the Bruins as a big-bodied shutdown defenseman that’s playing big minutes and in all situations for the Black and Gold. Adding Miller to the Bruins group would Carlo some company in the tough guy category and would also limit the amount of ice time they have to give to John Moore, who has been inconsistent for the Black and Gold since returning from shoulder surgery last month.

Haggerty: B's blown leads are concerning

There will be plenty of options for the Boston Bruins at the trade deadline when it comes to bolstering their top-6 attack.

Some seasons the B's have bagged a big target as they did a couple of years ago when they acquired Rick Nash from the New York Rangers, and there have been other seasons when more modest rental winger trades like Drew Stafford and Marcus Johansson have worked out very well for the Black and Gold.

But there is always a top target for the Bruins in each one of these trade deadlines since Don Sweeney took over as general manager, and this season will be no different for a B’s team sitting in first place in the Atlantic Division. The Rangers haven’t become sellers yet in the trade market, though there have curiously been rumors about the availability of backup goaltender Alexander Georgiev at this point in the season.

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But when they do become full-out sellers at some point in the second half of the season, big Rangers winger Chris Kreider will be the Bruins top option for a top-6 winger at the trade deadline, according to multiple hockey sources. It isn’t even a certainty that the Rangers will decide to part with a player that’s been a core member of their group since they selected him 19th overall in the 2009 NHL Draft, but it’s hard to imagine they would keep him given their status as a rebuilding franchise.

• Trade targets who could increase Bruins' toughness

The 28-year-old Kreider has the size at 6-foot-3, 218-pounds and he’s got the skating speed that the Bruins are looking for in every player on their roster.

Kreider has 16 goals and 31 points in 47 games this season for the Rangers, and is on pace for 28 goals and 54 points. He’s topped 20 goals four times during his career and surpassed 50 points a couple of times. Even better, Kreider represents a player that plays strong in front of the net and will bring a little edge to his game from time to time as well. The size, strength and skill combined with his background as an Eastern Conference player, a local kid and a former Boston College standout check many of the boxes for a Bruins scouting staff that seems to collect players just like Kreider on their NHL roster.

The one obvious drawback with Kreider is that his natural position is left wing, where the Bruins already have Brad Marchand and Jake DeBrusk on the top-6, but he would bring a different and much-needed element to that forward group given his style of play. It might push DeBrusk down to the third line and force guys like Danton Heinen and Anders Bjork to potentially play on the right side rather than the left side, but it would also undoubtedly strengthen their depth and overall quality of attack that will be needed in the postseason.

The other drawback for the Bruins is that Kreider will be in high demand as one of the top forwards on the rental market given his skill set, and that could mean the B’s will have to part with a first-round pick in order to ensure his acquisition.

Haggerty: These blown leads are concerning

PITTSBURGH — If it happened once or twice, it could be shrugged off as a coincidence.

But the Bruins have blown three-goal leads three times this season, including two in the last week alone. That gives them one of the NHL's worst records when leading after two periods, with seven losses already this season.

To put Sunday's 4-3 loss at Pittsburgh in perspective, the Bruins went into the contest 200-1-6 since 2010-11 in games where they’d held a three-goal lead. 

It came down to a couple different things on Sunday, but you can start with their sloppy second period. They basically did nothing for the first 10 minutes coming out of the first intermission. That opened the door for everything that followed.

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First, Sidney Crosby made a couple of All-World plays to set up goals and get the Penguins back in the game. Then, it came down to the Bruins dooming themselves with mistakes, allowing two more goals without any offensive response. 

On the third goal, their top power-play unit stayed out on the ice far too long, and a gassed Brad Marchand couldn’t catch Jack Johnson as the trailer unloaded a shorthanded bomb. Then in the third, Evgeni Malkin stripped Charlie McAvoy behind the Boston net and set up Bryan Rust for the Penguins' game-winner.

• McAvoy takes the blame: "I've got to be better for this team."

To a man, the Bruins said it wasn’t about taking the foot off the gas pedal. Instead, they pointed to mistakes made while crediting Pittsburgh for pushing back.

“It’s typically how does it happen? We saw some poor defending and some poor goaltending in Philly, and tonight it was more of the same to be honest with you,” said coach Bruce Cassidy. “Not so much on the goalie. They were good goals. But we get beat off the wall and the last one I can’t tell you what happened to be honest with you.

“I saw them bump their urgency up. The goals we are giving up against a good team…what is it a lack of focus? Do we lose our urgency? Because they are gifts a little bit. You can get outplayed by good teams, and you will in stretches. But these were gifts today.”

But it sure feels like the mind-numbing results fly in the face of their denials. Instead, something feels inherently wrong with a team that consistently plays down to the worst teams in the league, and seems to ease up once they build a comfortable lead. Those are the kinds of team traits that don’t go away as things get more challenging, and will certainly crop up when things are heightened. It’s also a shocking development for a Bruins team that’s been very good at closing out other teams over the years.

“We just need to bear down and you can’t just have a good effort and be satisfied with that, and then come back in the next game and just play for half of a game or whatever that was,” said Patrice Bergeron, who scored his 21st goal of the season and won 20-of-25 face-offs. “We need to take it upon ourselves. We all need to take responsibility and be accountable for how we’re able to play in this locker room.

“It’s one of those games where we’re playing a good team and they’re going to give you a push, but you can’t let that go by. It’s a 3-0 and you know there’s a lot of game left, so you need to play the right way and keep pushing in order to increase that lead.”

The good news for the Bruins is that they still have a half-season to figure things out. But it also makes one wonder if something has to change from the outside to improve things for a Bruins team that's almost the same as last season’s Stanley Cup finalist.

It remains to be seen what’s going to right the ship, or if it will ever get righted at all. But the list of problems is growing for a Bruins team that can’t live off its early-season success for much longer.

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