Hemsky scored his second goal with 34.9 seconds left to play, giving the Oilers a 4-3 win over the Columbus Blue Jackets on Tuesday night.
Hemsky added two assists, and Lubomir Visnovsky and Denis Grebeshkov also scored for the Oilers (24-19-3) who have won five of their last six to move back into a playoff position in the Western Conference.
"That was unreal, I haven't seen anything like that in a while," said Oilers head coach Craig MacTavish of Hemsky's performance Tuesday. "Two goals and two assists. We've seen that before. But not where all four are world-class plays.
"It couldn't have come at a better time. He single-handedly willed the win for us. It was a great effort from Ales."
The Oilers tied the game at 3 with 4:42 to play, just as a power play expired. Hemsky spotted a pinching Grebeshkov and he put everything he had into a shot that beat Steve Mason to tie the game 3-3.
Hemsky got the job done almost single-handedly at the end to give Edmonton the win as he came in on the right hand side and beat Mason up high.
"When you have four points or something like that you are always asked if it is the best game in your career," Hemsky said. "For me every game we win is what I feel good about. I just want to go out there and do my part. It felt great to win the game. It's a great feeling in this room right now."
Edmonton got out to an early lead, scoring on the power play five minutes into the opening period when Visnovsky sent a cross-ice pass to Hemsky, then crept in from the point for the return feed and blasted the puck past Columbus starter Mason.
The Blue Jackets tied it a minute and a half into the second, when Williams sent a shot into a crowd of players standing in the crease. The puck caromed to Boll and Roloson was unable to stop the tap-in.
Edmonton regained the lead in the middle of the second period as Hemsky sped past Fedor Tyutin and beat Mason on a backhander.
It didn't take long for the Jackets to knot the game again, as just a minute and a half later, Melhot blasted a shot past Roloson to make it 2-2.
Columbus took its first lead of the game with five minutes to play in the period, when Williams took a shot from in tight that Roloson waved at with his glove.
The Blue Jackets came close to going up by two midway through the third as a puck sneaked behind Roloson before Ladislav Smid fished it out. The play ended with Roloson throwing punches at Boll for crashing the crease.
"We pissed it away," Columbus coach Ken Hitchcock said. "We turned it over twice in the neutral zone and we gave it away. They had nothing going, we were completely controlling the hockey game. We gave it away. We had a turnover with 47 seconds left. You can't do that.
"We had a great third period, and we gave it away. Bottom line."
Columbus announced Tuesday that G Pascal Leclaire will have ankle surgery and is expected to be sidelined 10-12 weeks. Leclaire's operation is scheduled for Friday. ... The Oilers placed newly acquired G Dany Sabourin on waivers Tuesday. Sabourin came to Edmonton in a trade earlier in the week that sent Mathieu Garon to Pittsburgh. ... One game after Hemsky returned to the lineup following a concussion, the Oilers had another concussed forward back to play against Columbus as Robert Nilsson came back after a five game absence. ... The Blue Jackets were without rookie winger Nikita Filatov, out with a leg injury.