The Sharks rebounded from a 5-1 home loss to the Tampa Bay Lightning on Wednesday. Dell replaced Martin Jones in that game after the second period.
"I think it was a big bounce-back for the team after the last game," Dell said. "I think the one period I got in for that helped prepare [me for] this one."
Hertl gave the Sharks a 1-0 lead 48 seconds into the game with his third goal of the season and first since Oct. 17. Markstrom made a save on Ryan Braun's shot from above the right circle, but the rebound deflected off Hertl's skate and over the goal line.
"We need scoring by committee," Sharks coach Peter DeBoer said. "He's one of those guys. Tierney got a couple tonight, and Couture's been consistent all year. That's how we're going to win. I thought Tomas Hertl's been playing some really good hockey."
Couture made it 2-0 with a shorthanded goal -- San Jose's first of the season -- at 15:59 of the second period. Hertl chipped the puck out of the defensive zone, springing Couture on a breakaway. Couture faked left, went right and beat Markstrom between the legs with a backhand shot. It was Couture's first goal since Oct. 28. He leads the Sharks with 10 goals.
"He's a big strong guy, "Couture said of Hertl. "He had three guys on him, and he made a great chip. Fortunately it didn't go too far, so I was able to track it down and still have an angle to get to the net. Made a move I like to make and was able to find the back of the net."
Vancouver outshot San Jose 14-6 in the second period but couldn't get the puck past Dell, who made two stellar saves on 2-on-1 rushes. He stopped Sven Baertschi at 3:18 of the second on a power play and Derek Dorsett at 11:15 on a shorthanded try.
"Dell was our best player, which is why we have him," DeBoer said. "He was great. ... He had an exceptional season last year and followed it up with a great training camp and every time we've put him in there, he's given us good games. He's a big part of our team."
Couture scored an empty-net goal with 1:41 left in the third period. Tierney scored a shorthanded, empty net goal with 38.8 seconds remaining and on a penalty shot with 12.2 seconds left.