The Boston Bruins-Toronto Maple Leafs matchup in the first round of the 2019 Stanley Cup playoffs seemed preordained for months. Can the addition of John Tavares carry the rest of the Leafs to finally slay their demons? Let's break it down:

How they got here: The Bruins overcame injuries to the majority of their roster -- only four players appeared in more than 75 games, and none was a defenseman -- to again end up one of the NHL's top teams, with a 49-24-9 record and 107 points. They were third in goals against (2.59 per game) and 11th in goals (at 3.13) per game, fueled by Brad Marchand's 100-point season, David Pastrnak's 38 goals in 66 games and 73 points from David Krejci, matching his career high.

The Maple Leafs added free-agent prize John Tavares last summer but struggled with consistency this season, especially on defense. They were fourth in the NHL in goals per game at 3.49 but a middling 12th in goals against (3.04). They generate as many shots (33.4) as they surrender (33.1). The Leafs are a 100-point team (46-28-8), and they have a deep forward group and a capable goaltender. But are they good enough defensively to win this war against the rival Bruins?

First line: In the past, we might have skipped to the "Advantage: Bruins" part of this entry, but the line of Patrice Bergeron, Marchand and Pastrnak was actually a bit less effective than it was in dominating the league last season. Its goals-for percentage dropped form 63.64 to 53.85. Metrics such as expected goals for percentage (56.28) and high-danger shot attempt percentage (54.07) at 5-on-5 dipped as well. Granted, they played 462:16 together compared to 535 minutes in the previous season due to injuries. The Toronto line of Tavares, Mitch Marner and Zach Hyman played 817 minutes together and was outstanding: 60.92 goals-for percentage, 56.82 high-danger shot attempts percentage and 53 goals generated. Basing this strictly on their play this season? Advantage: tie

Depth: The Leafs have their greatest advantage at the forward spot. Beyond Marner (94 points) and Tavares (88) is Auston Matthews (73 points in 68 games), who skated with combinations of Andreas Johnsson, Kasperi Kapanen and William Nylander. Nazem Kadri, who was suspended for three games in the playoff series against the Bruins last year, and Patrick Marleau lead the third line. After their top line, the Bruins' best duo has been Krejci and Jake DeBrusk, who had 27 goals in a breakout campaign. Danton Heinen, Charlie Coyle, Marcus Johansson, rookie Karson Kuhlman and Sean Kuraly (currently injured) can all contribute. Noel Acciari and veteran David Backes, if he plays, are among the grinders. Advantage: Maple Leafs

Defense: As much as the forwards are an advantage for the Leafs, the blue line is an advantage for the Bruins. The depth of this group was on full display through a season of injuries, as only one defenseman (Brandon Carlo) played more than 70 games. It'll be tested again, as Kevan Miller will likely miss the start of the series. Zdeno Chara and Charlie McAvoy are the top pairing, with Torey Krug (53 points) and Carlo next. Matt Grzelcyk will likely pair with Steven Kampfer, with Miller and John Moore out. For the Leafs, Morgan Rielly (72 points) and veteran (some would say liability) Ron Hainsey form the top pairing, with Jake Muzzin and Nikita Zaitsev as the second duo, followed by Travis Dermott and Jake "minus-5 in Game 7 last year" Gardiner as the other duo. Advantage: Bruins

Goaltending: The Bruins had the seventh-best team save percentage in the NHL, at .912 with nine shutouts. Tuukka Rask (27-13-5) was good, but backup Jaroslav Halak was even better (22-11-4), with a .922 save percentage and 16.30 goals saved above average. Frederik Andersen of Toronto once again faced a ton of shots (1,958) and made a ton of saves (1,796) for a .917 save percentage, often being the best player on the ice for the Leafs. His goals saved above average at 5-on-5 was 9.88. But the Bruins' duo is just a shade better. Advantage: Bruins

Coaching: Bruce Cassidy deserves a massive amount of credit (and perhaps a Jack Adams nomination) for leading the Bruins through their injuries to tie for second in the NHL in points. Mike Babcock, meanwhile, is starting to hear it from the critics who wonder about the Leafs' player usage and defensive stability. He is one of the most respected coaches in the NHL ... and one who hasn't won a playoff round since Nicklas Lidstrom retired. Advantage: Bruins

Health: The Bruins are without Miller, center Sean Kuraly and defenseman John Moore to start the series, but all could be back at some point. Toronto is fairly healthy. Advantage: Maple Leafs

Special teams: The Bruins have the third-best power play in the NHL, at 25.9 percent, while the Leafs are eighth, at 21.8 percent. Their penalty kills had identical 79.9 percent rates, though the Bruins were short-handed more times (244) than the Leafs (204). Advantage: Bruins

Prediction: Maple Leafs in seven. Andersen is the key to this series, as Toronto has no alternative in goal and because he has been the team's best defense all season. If he's able to steal a couple of games, this Toronto offense was second only to the Lightning in 5-on-5 goals per 60 minutes (3.03). The Buds pull the upset.