What to know about the Maple Leafs, Bruins’ 1st round opponent

For the fourth time in 12 seasons, the Bruins and Maple Leafs will collide in the first round of the Stanley Cup playoffs, starting with Game 1 Saturday at 8 p.m. at TD Garden.

Toronto has not won a playoff series against Boston since 1959, with the Bruins triumphing in seven games in 2013, 2018, and 2019.

Even though it’s been five years since their last postseason showdown, the Maple Leafs’ DNA hasn’t changed much, with a roster buoyed by elite forwards but marred with flaws at the other end of the ice.

Here’s what you need to know about the Bruins’ familiar first-round foe:

Toronto’s greatest strength is offense — especially at five-on-five

It’s no surprise that a team anchored by Auston Matthews (69 goals, 107 points), William Nylander ( 40, 97), Mitch Marner (26, 85), and John Tavares (28, 64) relies heavily on its high-powered offense to put opponents on the ropes.

The Bruins will have their work cut out when it comes to allocating defensive-zone reps for blue liners Brandon Carlo, Hampus Lindholm, and Charlie McAvoy — especially with Maple Leafs coach Sheldon Keefe sprinkling his top forwards across the depth chart.

Toronto also has received secondary scoring and much-needed jam with Max Domi (47 points) and old friend Tyler Bertuzzi, who has 14 goals and 21 points over his last 25 games.

Despite their high-end talent, the Maple Leafs aren’t a rush-heavy team, doing most of their damage with a steady dose of shots from the slot and Grade A ice.

Toronto is one of the best teams in the league at five-on-five play, ranking seventh in goal differential (plus-33), per Money Puck.

If the Bruins are going to hold off Toronto’s potent offense, they’re going to need their D-zone structure to hold its own at the net front.

The Bruins relinquished 11.42 five-on-five high-danger scoring chances per game this season, which ranked 24th (per Natural Stat Trick). The Leafs, meanwhile, averaged 12.61 high-danger chances at five-on-five, third in the league.

The Bruins’ lackluster slot protection has been covered up by the play of goaltenders Linus Ullmark and Jeremy Swayman. But the Bruins will be playing with fire if those lapses continue.

The defense is in flux

Though Toronto has added some heft on the blue line with 6-foot-5-inch Joel Edmundson, Simon Benoit (245 hits), and Jake McCabe (129 blocks), it is still a relatively pedestrian defensive club.

The Bruins rank sixth in goals against per game (2.70), while Toronto is 20th at 3.15. Some of those faults might be attributed to goaltending, but Toronto also is 17th in five-on-five high-danger scoring chances allowed per game at 11.19.

Keefe has some decisions to make when it comes to choosing the top six defensemen for the playoffs. This season, Toronto rolled out a whopping 20 different D-pairings that logged at least 50 minutes of five-on-five ice time, per Natural Stat Trick.

There are some problems on special teams

For all of the firepower up front, Toronto’s power play has fallen into a major rut, cashing in only 13 percent (9 of 69) of its bids in the last 22 games. Even the Bruins’ slumping power play was stronger over a similar stretch (17.9 percent since March 2).

But the Bruins’ penalty kill still will have its hands full against the Maple Leafs’ power play, which ranked seventh overall this season at 24.3 percent. Toronto was 1 for 11 on the power play against the Bruins this season.

Toronto’s penalty kill has been an issue all season, ranking 23rd at 76.9 percent. The Bruins’ power play cashed in on 30 percent of its opportunities while sweeping four games against Toronto in the regular season.

There are question marks in net

The most jarring difference between the Bruins and Maple Leafs is between the pipes.

While the Bruins boast arguably the best goalie tandem in the league with Ullmark and Swayman, Toronto has yet to identify a solid option between Ilya Samsonov and Joseph Woll.

Samonsov posted an .890 save percentage over 40 games this season, and is just 1-2-2 with an .899 save percentage against the Bruins over seven career games.

Woll, who played three seasons at Boston College, has stronger numbers this season (.907 save percentage over 25 games, .890 since the All-Star break). But the 25-year-old is 0-2-1 with an .865 save percentage and a 3.97 goals-against average against the Bruins in his career.

Even with Toronto’s impressive offense, the Leafs’ success may not translate to the postseason if Woll and Samsonov can’t keep them afloat in tight contests.

Down the other end of the ice, Ullmark has been on a roll since the trade deadline — going 6-3-0 with a .935 save percentage. But it’s Swayman who has had Toronto’s number over the last two seasons. The Bruins have won seven straight against Toronto, with Swayman going 4-0-0 with a stellar .961 save percentage.