As a result, they held on for a 4-3 victory over Detroit and a reminder of how thin the margin for error is in the NHL these days.
It was the third straight victory for Toronto to kick off an important stretch of games and kept the team in playoff position heading to the second half of the season.
"This is where the stakes kind of go up," Lupul said. "This is the more fun part of the year. This is where you want to play your best hockey.
"We've put our team in the position where we can be a playoff team, but all we've done right now is set ourselves up."
Toronto is seventh in the Eastern Conference, but remains among a cluster of six teams separated by just four points.
That's what made Saturday's victory over Detroit so big, especially after the Leafs built a 3-0 lead in the first period and let it slip away.
"I think we handled it really good," said goalie Jonas Gustavsson, who made 37 saves. "[Lupul] came up with a really big goal and we kept battling the whole game."
The winner came less than three minutes after Detroit had tied it 3-3.
Everything appeared to be heading in the wrong direction for Toronto when Lupul stole the puck from Henrik Zetterberg and scored his 19th goal of the season.
From there, Gustavsson preserved the victory with a big glove save on Johan Franzen in the final minute.
"That one chance with about 40 seconds to go made my heart stop," Leafs coach Ron Wilson said. "But the Monster came up big."
The Red Wings quickly boarded a flight for Chicago, where they face the Blackhawks in a big game Sunday, and weren't very happy with their performance.
"That was un-Red Wing-like," coach Mike Babcock said. "You can't win every night in the league playing like that."
The Leafs had a strong start with Kessel converting a penalty shot at 4:30 of the first before Phaneuf hammered home a power-play goal at 8:19.
The Leafs captain was an unlikely contributor after taking a puck in the cheek on Thursday and having to play with a long visor to cover the big lump on his face.
"Once I knew nothing was broken, I knew I was going to play," Phaneuf said.
After Steckel scored to make it 3-0, Babcock called a timeout to try and wake up his players.
"We had a great opportunity," he said. "But the hockey gods treat you right -- you don't start on time you don't win that often in this league. We weren't good enough."
The Leafs were fortunate to come out on top after being outshot 40-18.
But the team seems to have developed a resilient spirit -- "we're a group that definitely does not quit," said Phaneuf -- something that gave Gustavsson confidence even after he allowed Hudler to tie it early in the third period.
During the first half of the season, he's learned to trust his teammates.
"I always believe in our team," Gustavsson said. "They showed me so many times they score a lot of goals. You just have to keep believing."
- With defenseman Mike Komisarek returning to Toronto's lineup for the first time since Nov. 17, Jake Gardiner was a healthy scratch.
- Mike Brown also returned from injury for the Leafs.
- Tomas Holmstrom and Darren Helm sat out for Detroit with groin strains.
- Howard has 99 career NHL victories.