Hannan was happy to get a rare offensive highlight - yet he knows the Sharks wouldn't survive such a sloppy, exhausting performance in the playoffs.
Patrick Rissmiller had a goal and an assist, Jonathan Cheechoo added a goal and the Sharks kept pace in the tight Pacific Division race with a 4-2 victory over the Phoenix Coyotes.
Christian Ehrhoff also scored as San Jose earned its 100th point of the season with its eighth victory in 10 games despite committing nine minor penalties - a rarity for one of the NHL's least-penalized clubs.
Hannan scored just his third goal of the season to break open the game early in the third period. He preferred to see the outing positively - as a chance to fine-tune the penalty-killing unit for the playoff struggles ahead.
"We did a good job, but you don't want to be killing that many penalties," said Hannan, whose previous two goals this season both went into empty nets. "There's mistakes that we need to take out of our game."
Evgeni Nabokov made 25 saves, and Joe Thornton set up Cheechoo's seventh goal in five games with his NHL-leading 84th assist in the Sharks' fifth straight home victory.
Fredrik Sjostrom and Steven Reinprecht scored for the Coyotes, who have the Western Conference's worst record after losing for the 13th time in 15 games despite spending much of the night on power plays against the surprisingly sloppy Sharks. Curtis Joseph stopped 21 shots, but lost for the eighth time in 10 starts.
"We seem to always find a way not to get it done," Joseph said. "They just kept coming and charging."
Phoenix played the last 63 seconds with a 6-on-3 advantage after pulling Joseph, but still couldn't get the puck past Nabokov. The San Jose goalie stopped four scoring chances in the final moments, earning a standing ovation after the buzzer.
"We're not very good," Coyotes coach Wayne Gretzky said. "We don't shoot the puck enough at opportune times. We don't crash the nets. We don't simplify the game, and you're not going to score."
San Jose bettered last season's 99-point total in front of another sellout crowd, ensuring just the second triple-digit finish in franchise history. With four games left - including three at home - the Sharks have a good chance to surpass their club-record 104 points in 2003-04.
But winning a division title or getting home-ice advantage in the playoffs seems less likely. The Sharks are tied with Dallas for fifth place in the conference standings, but the Stars have a game in hand - and Anaheim leads both of its division rivals with 104 points.
The Sharks visit the Ducks on Wednesday night.
Rissmiller, a solid checking forward completing his first full NHL season, capitalized on his linemates' persistence for the game's first goal early in the second period. Curtis Brown forced a turnover at the Phoenix blue line, and Mike Grier got the puck to Rissmiller for a breakaway score, his sixth of the season.
The trio's line was broken up last week on the road, but rebounded with an impressive game.
"We've played better as of late," Rissmiller said. "We can get the job done."
Sjostrom broke up Nabokov's shutout bid late in the second period with a long shot from the boards, but the Sharks' checking line produced another goal early in the third period when Grier found Hannan.
"We need scoring from more than one line a night," Sharks coach Ron Wilson said. "Tonight, it was spread around a little bit, and that's a positive for us. ... We got to work on our penalty-killing, too. Not by choice, that's just the way it went. We shouldn't be killing nine penalties, especially with some calls out of nowhere."
Cheechoo got his 32nd goal just 68 seconds later, chasing down Thornton's pass and beating Joseph in the top corner of the net. Reinprecht added his ninth goal during a two-man advantage midway through the period.
Notes: Sharks D Craig Rivet, who has six points and a plus-5 rating in 13 games since joining the club in a trade with Montreal, sat out with a minor groin injury. ... Rissmiller's goal was his first since Feb. 21. ... Marc-Edouard Vlasic, the Sharks' impressive rookie defenceman, celebrated his 20th birthday with an assist on Ehrhoff's goal.