Kadri scored 2:51 into overtime and the Toronto Maple Leafs beat the Boston Bruins 4-3 on Thursday night.
''We're alive, but there's a lot of things that have to go our way,'' Toronto coach Randy Carlyle said. ''Make sure that we don't get too far ahead of ourselves. We've only won two games here.''
Bergeron tied the game at 12:51 of the third against backup goalie James Reimer, after Lucic scored 5:03 into the final period.
''It showed some character to be able to come back against a desperate team like Toronto,'' said Bruins forward Milan Lucic, who scored Boston's second goal of the night 5:03 into the third. ''These are the type of the situations you can find yourselves in in the playoffs.''
The Bruins have all but clinched home ice throughout the first three rounds of the playoff. In losing back-to-back games for the first time since Feb. 26 and March 1, Boston might've picked up a vital lesson after a month filled with so much winning.
''It's adversity that we're going to face in the playoffs,'' Bergeron said. ''We've got to make sure that we realize that.''
Paul Ranger, Tyler Bozak and James van Riemsdyk scored for Toronto, which lost goaltender Jonathan Bernier midway through the third.
Van Riemsdyk reached the 30-goal plateau for the first time in his NHL career. His previous career high was 21, set with the Philadelphia Flyers in 2010-11.
It remains to be seen how severe Bernier's injury is. He left 7:22 into the third period after Ranger pushed Patrice Bergeron into him. Carlyle would only say was a lower-body injury and that the goaltender would be getting an MRI.
Bernier recently missed five straight games with a groin injury sustained March 13 in Los Angeles.
James Reimer replaced him and stopped 10 of the 11 shots he faced.
''I tried to hold the boys in there and keep it close,'' Reimer said. ''I had faith in the boys. They pulled it out, and obviously it was a good feeling.''
Toronto (38-32-8) improved to 84 points with its second straight victory, a very important one after eight straight regulation losses sent the season off the rails. But the Leafs didn't get any help in their playoff quest, as the Columbus Blue Jackets beat the Philadelphia Flyers to get to 85 points and remain in the Eastern Conference's second wild-card spot.
The Blue Jackets also have two more games to play - six to the Leafs' four.
''We've won two in a row now, so that's a starting point,'' Bozak said. ''We have huge games coming up here to end the season. But that was a tough test for our team tonight, and we were able to come out on top.''
NOTES: Joffrey Lupul was scratched with a lower-body injury. The 30-year-old winger played 18:32 in Tuesday's game against the Calgary and participated in Thursday's morning skate but was the first player to leave the ice. ... Boston's Jarome Iginla returned to the Bruins' lineup after missing the Bruins' 3-2 loss to the Red Wings with what the team called a lower-body injury. ... Bruins F Carl Soderberg returned to Boston for the birth of his child, which meant Jordan Caron played his second straight game.