Question: How does a team lose a basketball game in which it makes 60 percent of its shots? Answer: when it turns the ball over a lot, misses too many free throws and has multiple key players make a negative impact, then also allows the opponent to shoot a high percentage on a lot of open three-pointers, get to the basket with ease, run its offense essentially unbothered and score 120 points.

Yeah, the Bucks lost Game 2 of their first-round playoff series Tuesday night against the Celtics, 120-106. And when Jaylen Brown, who had the biggest game of his young career, banked in a three-pointer from the right wing to put Boston up by 19 points and a grin on his face with 2:27 remaining at TD Garden, you knew two things: it was the Celtics’ night, and Milwaukee is in trouble.  

For a series many saw as a likely potential upset, considering second-seeded Boston’s injuries – with its two stars, Kyrie Irving and Gordan Hayward, out and another important player, Marcus Smart, still sidelined – and seventh-seeded Milwaukee’s supposed talent advantage (read: Giannis Antetokounmpo advantage), Game 2 played out distressingly like Game 1, just without the dramatic ending. 

The Bucks seemingly made no adjustments after their opening defeat. They started the same five players, despite the dreadful performance of their backcourt; were again careless with the ball, committing seven turnovers in the first quarter; and once more let a depleted Boston offense jump out to a double-digit early lead. Milwaukee made it interesting at times, thanks to the scoring tandem of Antetokounmpo and Khris Middleton, but never truly threatened the Celtics, who were steadily in control the whole night.

While the Bucks lacked any team identity – or, frankly, gameplan – other than hoping Giannis could will them to a win, Boston was composed and efficient, exploiting Milwaukee’s weaknesses and mistakes. The Celtics’ average age is actually 0.5 years younger than the Bucks’, but because of superior coaching, well-defined roles and rotations and an expertly executed system – plus the undeniable, if overlooked, ability on its roster – Boston played like the skilled and experienced varsity, schooling a talented-but-undisciplined JV squad. 

Even without its best players, Boston plays as though it knows exactly who it is and what it’s doing – defending and rebounding as a team, shooting threes and scoring in the paint. The Celtics were a simply better team on just about every possession Tuesday night, and they now hold a 2-0 series advantage. In their teams’ playoff histories, Boston is 35-0 when leading 2-0, while the Bucks are 0-13 all-time when down 0-2. 

The teams head to Milwaukee for Friday’s Game 3 and Sunday’s Game 4 at the BMO Harris Bradley Center, as the Bucks try to figure out how to get back into this thing. It’s an easy criticism to say they haven’t played well enough to win, and an easy observation to say they have to try something very different when they get back home to do so.

1. Something I liked

The Bucks’ top dogs played that way in Boston. Antetokounmpo and Middleton, who scored 30 and 25, respectively, on Tuesday, combined for a colossal 121 of Milwaukee’s 213 points in Games 1 and 2.

You certainly don’t want two players accounting for 57 percent of your scoring (see: next item) but it’s heartening that – in the playoffs, when the best players are the most impactful – Giannis and Khris are showing up and shooting well (61.3 field-goal percentage).

2. Something I didn’t like

Going into this series, the main Bucks storyline was that Giannis needed help from his supporting cast. Not only has he not gotten help, the auxiliary players around him have actually hurt the team. Eric Bledsoe, Tony Snell and Jabari Parker – three of Milwaukee’s six most-vital players – have been net-negative contributors, with Bledsoe pressing and Snell and Parker disappearing. 

Bledsoe has missed 16 of 25 shots, while committing eight fouls and six turnovers to just eight assists in two games; Snell and Parker have combined to make three baskets in 80 minutes. Parker, somehow, has become almost unplayable. This is a significant problem.

3. Something I’m looking at more closely

We already knew Boston, with Brad Stevens, would have the coaching edge on Milwaukee and interim head coach Joe Prunty. We knew the Celtics, who led the league in free-throw percentage during the regular season, would gladly take free shots on offensive possessions and best the Bucks at the line. But we didn’t expect Boston’s bench to outperform the Bucks’ so dramatically. 

Through two games, Celtics reserves have 68 points, compared to Milwaukee’s 48. On Tuesday night, three Boston backups scored in double figures, including Marcus Morris, who has poured in 39 points in two contests. Milwaukee has its full roster healthy and available, and it emptied out its bench in Game 2 searching for a spark. If Prunty doesn’t find one – especially with the usual offensive options struggling, players like Malcolm Brogdon and Shabazz Muhammad become more important – the Bucks are done.

Game 3 in Milwaukee is at the BMO Harris Bradley Center at 8:30 p.m. (ESPN).