Slipshod defense for much of the third period enabled the Ducks to filch the 2 points, and had coach Marco Sturm shaking his head at night’s end.

“We played OK,” a disappointed Sturm said in his postgame interview on NESN. “We just had moments in our defensive zone, and I don’t care if you have twice the amount of shots or chances . . . if you can’t defend, or don’t want to defend, then you are going to end up with a game like today.”

Get Starting Point

A guide through the most important stories of the morning, delivered Monday through Friday.

For no apparent reason, added Sturm, panic overtook his club late in the game in the defensive end.

“We had some mistakes, especially the last 5-6 minutes,” he said. “We just have to manage it better.”

Morgan Geekie’s second power-play goal of the night, with 7:39 gone in the third, pulled the Bruins into a 3-3 tie.

Goals by Geekie and Mikey Eyssimont across the opening 40 minutes kept the Bruins within reach, trailing the Ducks, 3-2, entering the third period.

Geekie has 14 goals in 22 games, a pace well ahead of the career-best 33 he scored last season. He is tied with Nathan MacKinnon (Avalanche) and Leon Draisaitl (Oilers) atop the league’s goal-scoring list. The proud son of Starthclair, Manitoba, has 47 goals in his last 99 games in Black & Gold.

Stop No. 2 of the four-game trek will be Friday night in Los Angeles.

Earlier in the day, Bruins coach Marco Sturm confirmed that No. 1 defensemen Charlie McAvoy underwent facial surgery and is lost from the lineup for an indefinite period — likely at least a month. McAvoy was drilled in the face by a Noah Dobson slapshot on Saturday night in Montreal.

After falling into a 3-1 deficit late in the middle period on Ryan Strome’s power-play goal at 13:47 — Mason Lohrei was off for tripping — Eyssimont countered at 18:27 with his fifth of the season.

The Bruins peppered Ducks tender Lukas Dostal with 18 shots in the opening 20:00, but Anaheim potted two of the 11 they landed on Korpisalo and carried a 2-1 lead into the first intermission.

For the third time in their last four outings, the Bruins surrendered the game’s opening goal. Jansen Harkins, originally a Jets draft pick, connected with 2:29 gone on the Ducks’ second shot of the night.

Four minutes after Harkins, the Ducks made it 2-0 on a strike by menacing defenseman Radko Gudas. The climb uphill grew steeper.

Finally, with 5:02 to go before the first intermission, Geekie cut the Ducks lead in half less than a minute after ex-BC blueliner Drew Helleson was whistled to the penalty box for cross-checking Fraser Minten.

The power-play goal extended to six the number of games in a row the Bruins have scored on the advantage.

It’s the Black & Gold’s best streak since Nov. 4-18 in the record-setting 2023-24 season, when they also clicked in a season-best six consecutive games. They went 8 for 23 (34.8 pct) in that stretch and improved their season record to 13-1-2.

Boston is a sizzling 9 for 20 in these last six games, with Geekie’s two Wednesday joined by David Pastrnak (two), Eyssimont, Pavel Zacha, Hampus Lindholm, Viktor Arvidsson, and Riley Tufte.

Headed into the night, the Bruins power play tied for fifth in the NHL with 25.4 pct. efficiency.

Ex-BC winger Chris Kreider, dealt to the Ducks in June, connected for only 22 goals last season for the Rangers. He already has 10 and leads the Quack with five power-play strikes. The 34-year-old had a league-best 26 on the power play in 2021-22.

Since entering the league full-time in 2013-14, Kreider is tied for sixth in PPGs with 121. Pastrnak stands No. 5 with 127. The leader: Alex Ovechkin (199).

Kreider was injured and not in the lineup when the Ducks visited Boston on Oct. 23. The 7-5 loss, led by Mikael Granlund’s 2-3—5 tour de force, was the sixth straight for the Bruins, which they followed with seven straight wins.

Nikita Zadorov (seven) and Jeffrey Viel (six) accounted for a third of Boston’s 39 shots.

Kevin Paul Dupont can be reached at kevin.dupont@globe.com.