With seven seconds on the clock and a one-point lead, Boston Celtics forward Jaylen Brown stared down Toronto Raptors forward DeMar DeRozan. The back-and-forth battle between two of the Eastern Conference’s best would come down to the final shot. The Raptors’ three-time All-Star dribbled to his left, faked a spin-move on the Celtics’ 21-year-old forward, and fired a fade-away jumper — short. The ball bounced off the rim and into the hands of forward Serge Ibaka, who was quickly swarmed by Boston’s forward Jayson Tatum and guard Marcus Smart. Tatum reached for the ball, tipping it out of Ibaka’s hands, and as time expired Smart grabbed control — sealing the Celtics’ 12th straight win, 95-94, over the Toronto Raptors.

After forward Gordon Hayward’s gruesome injury and the ensuing two losses, the Celtics made National Basketball Association history, becoming the first team to win seven straight games after starting 0-2.

Now, nearly two weeks since their record-breaking resurrection, the Celtics still have not lost. After Sunday night’s win against the Raptors brought the streak to 12 wins, to call this team resilient would be an understatement — they’re legitimate contenders for the championship this year and do not appear to be slowing down.

With a stifling defense (they’ve allowed a league-low 94.0 points per game) and impressive rebounding (they rank only behind the Portland Trailblazers in rebound rate), head coach Brad Stevens’ young and deep squad has exceeded all expectations, and will enter Tuesday night’s game against the Brooklyn Nets with a league-leading 12 wins.

While the streak as a whole has been impressive, perhaps no games have been more so than the last few: with veteran forward Al Horford (concussion) missing games against the Los Angeles Lakers and Charlotte Hornets, and point guard Kyrie Irving (facial fracture) sidelined for Sunday’s game against the Raptors, the Celtics still managed wins in all three. “They are the best team in the NBA right now,” Toronto guard Kyle Lowry said. “They are playing unbelievable. Everybody is picking up slack.” 

Although plagued by injuries, everyone on the roster has proven that they can contribute. Down the stretch in a tight game against Toronto, the entire team stepped up to pull out the win, especially the 19-year-old rookie Tatum: “He made some big plays down the stretch,” teammate guard Terry Rozier said. “He’s got some heart man. He’s been getting better every day.” Rozier had a game himself Sunday night, scoring 16 points off the bench and impressing from beyond the arc. Horford returned to the team with a team-high 21, while also dishing out four assists. Brown was the second-leading scorer with 18, followed by Smart with 14. While they only shot 40.2 percent from the field, the team made up for it on the glass.  The Celtics outrebounded the Raptors 46-36, including 15 offensive boards as opposed to the Raptors’ six.

The Celtics’ performance was reminiscent of the season itself: “It couldn’t have gotten worse,” said Stevens about the Celtics’ shooting in the first half. But they pulled together and got it done: “We started at the bottom of the mountain, and tried to work our way up.”

The gritty Boston team is well on its way up that mountain, with Horford healthy and Irving set to return soon, as the unlikely Eastern Conference front-runners will look to power through a tough November. They host the Golden State Warriors Thursday night before a week-long road-trip.