Count the as the latest NHL elite to be absolutely confounded by the eighth-seeded Panthers.
Following their first-round upset of the top-seeded Boston Bruins, the Panthers beat the Leafs, 3-2, on Thursday in Toronto to take a 2-0 series lead in the Eastern Conference semifinal.
Of particular concern to Leafs head coach Sheldon Keefe was a pitiful second-period performance, in which the Panthers scored two unanswered goals.

'Disappointing.

Baffling,' Keefe said. 'We didn't make those mistakes one time in the last series [in the first round against Tampa].'
Sergei Bobrovsky made 35 saves for Florida, while Anton Lundell had a goal and an assist. Aleksander Barkov and Gustav Forsling also scored for Florida.
Florida Panthers defenseman Gustav Forsling (42) celebrates with teammates after scoring
Ryan O´Reilly and Alexander Kerfoot scored for Toronto, which blew an early 2-0 lead.

Ilya Samsonov stopped 26 shots.
The best-of-seven series shifts to Sunrise, Florida, for Game 3 on Sunday. Game 4 is scheduled for blur crypto punk Wednesday.
Toronto led 2-1 following a spirited, chippy first period.
Trouble found the Maple Leafs in the second.
Barkov tied the game 19 seconds into the period on a long shot for his second goal of the postseason. Less than a minute later, there was some sloppy play by Toronto in the defensive zone when Mitch Marner flipped an ill-advised pass to Auston Matthews, who couldn´t get it out of the zone.
Florida quickly countered as Forsling finished off a setup by Matthew Tkachuk - his fourth of the series - for his second and a 3-2 lead.
The Maple Leafs took a while to recover before William Nylander hit the post with a shot that also hit Bobrovsky in the back and stayed out.

Florida defenseman Brandon Montour then hit the post at the other end.
Toronto captain John Tavares had a great chance in front before Josh Mahura took a Nylander shot off the visor that left a trail of blood on the ice as he exited for the locker room.
The Panthers defenseman returned for the third period.
Florida's Josh Mahura took a Nylander shot off the visor that left a trail of blood on the ice
Toronto came out for the third with plenty of urgency, but couldn't solve Bobrovsky, who has started to rediscover his Vezina Trophy-winning form in these playoffs after losing the starting job late in the regular season to third-stringer Alex Lyon.
Tavares was stopped in alone and Nylander hit another post.

The Maple Leafs winger was also denied in tight with five minutes left in regulation.
Toronto continued to press with Samsonov on the bench for an extra attacker, but couldn´t beat Bobrovsky.
Toronto dropped the series opener 4-2 at Scotiabank Arena, but got off to a fast start Thursday when Kerfoot scored on the rebound of a Luke Schenn point shot for his second at 2:20 of the first.
Unable to connect on two early power plays in Game 1, the Maple Leafs made it 2-0 on a man advantage at 5:10 when Marner found O´Reilly, who scored his third on a one-timer.
The Panthers, who beat the record-setting Boston Bruins in seven games to make the second round, started to push back as the period wore on, including Sam Bennett putting Matthew Knies in a headlock and slamming him to the ice.
The Toronto rookie finished the period, but didn´t return for the second period due to an undisclosed injury.
Florida responded at 11:13 when Lundell scored his first after linemate Eetu Luostarinen crushed Leafs defenseman Timothy Liljegren behind Samsonov´s net and Tavares fell.
Panthers' Matthew Tkachuk (19) carries the puck past Maple Leafs' Morgan Rielly (44)
STARS 4, KRAKEN 2
Joe Pavelski scored his fifth goal in two games since returning from concussion protocol with an assist from Wyatt Johnston, his 19-year-old rookie housemate who also scored a goal, and the Dallas Stars beat Seattle 4-2 on Thursday night to tie the second-round series at a game each.
Evgenii Dadonov added a nifty wraparound goal and Tyler Seguin scored for the Stars, who like in their first-round series against Minnesota bounced back from an overtime loss at home in the opener to get even before hitting the road.
Game 3 is Sunday night in Seattle.
Tye Kartye and Jordan Eberle had goals for the Kraken.
Johnston, who has lived with Pavelski's family this season, set up his mentor's power-play goal when he initially whiffed at the puck before whipping around and sending it into the laid-out stick of goaltender Philipp Grubauer.

Pavelski was there for the rebound and put the Stars up 3-1 with 3:03 left in the middle period.
Pavelski scored all four Stars goals in Game 1, when they lost 5-4 in overtime. That was the 38-year-old forward's first game since banging his head hard on the ice after a big hit in the opener of the Minnesota series April.
17.
Jake Oettinger had 25 saves for the Stars. Grubauer stopped 33 shots.
Before Pavelski's latest goal, Kartye got the Kraken within 2-1 on a break when he took a long pass off the boards from Vince Dunn and got around defenseman Miro Heiskanen to score.
Joe Pavelski (left) scored his fifth goal in two games since returning from concussion
Johnston's second career playoff goal came right after the end of a power play earlier in the second period for 1-0 lead.

His 24 goals in the regular season tied for the NHL rookie lead.
Colin Miller had taken the shot from the top of the circle to the right of the net after he had gotten a cross-ice pass from Max Domi from the opposite circle.
Johnston initially got his blade on the puck, knocking in his own rebound after it ricocheted off Grubauer's chest.
Dadonov, a trade deadline addition, got his fourth goal of the playoffs when he skated around the net and sent the puck sliding across the line — and finally over it — for a 2-0 lead.
Seguin put the Stars up 4-1 with his fifth goal this postseason, the first at even strength, midway through the third period.

The veteran center, the only Dallas player who has won a Stanley Cup, also had an assist.