The journeyman wasn't having a particularly good game -- he shot 2-for-10 from the field -- and the Warriors were having a bad quarter, having been outscored 26-17.
But if Steph Curry is the breakout star of this postseason, then Jack -- who sealed the win with his two clutch free throws -- has proved to be an invaluable X factor and someone the San Antonio Spurs need to be thinking about.
Coming into the postseason, Jack averaged 12.9 PPG on 45 percent shooting. But in the series against Denver, he upped his play to 18.8 PPG on 53 percent shooting, plus 7 assists and 5.2 rebounds a game. He scored at least 20 in each of the four games he started. When David Lee went out with a hip injury in Game 1, conventional wisdom suggested sweep. But playoff basketball has a way of turning commoners into knights, and Jack is the latest example.
"The morning of the game , coach [Mark Jackson] came to me and said he was going to insert me in the starting lineup and to be aggressive, and that is my mindset," Jack told me. "I wasn't trying to replace the contributions David gave us, I was just trying to be more of a scorer, and it's been working out."
In his seven previous seasons, 2010-11 was the only time Jack had been to the playoffs. And in those six games with the New Orleans Hornets, he scored only 35 points on 35 percent shooting. Needless to say, no one expected him to go off against Denver.
Jack has always provided good D. But with Denver, and now most likely the Spurs, concentrating its efforts on keeping the ball out of Curry's hands, his offense and playmaking are crucial. One good sign for Warriors fans: Jack averaged almost 10 assists and 17.5 points on 50 percent shooting in four games against San Antonio this season as the teams split the regular-season series 2-2. So yeah, Curry gets the headlines -- deservedly so -- but quiet as it's kept, the Warriors are not going far without Jack.
"I would love to say that I've been just waiting for this to happen, but I'm almost as surprised as everyone else," he said, half-jokingly. "I always say that I work hard so that I'm better than I'm supposed to be. I guess between that, the system I'm in and the fact the players I'm with attract so much attention that I'm able to help the team offensively a whole lot more."
It has to be weird to go from a journeyman bouncing around five teams to someone other teams have to account for. Just as it must be weird as a team to go from an afterthought to a darling. But Jack said no one is paying attention.
"I remember something Ty Willingham said and that is 'We don't need to succumb to the expectations of others,'" Jack said. "When we started, our goal was making it to the postseason and then after that it was a toss-up. Those were the goals we set up from the beginning of the season. They gave us zero percent chance to make the playoffs. They thought we'd be some cute little team but not do anything. But we don't worry about the expectations of others; we only worry about our locker room."
So now the Warriors are past Denver -- great.
But if San Antonio -- which has home-court advantage and hasn't lost at home to the Warriors in the Tim Duncan era -- trips them up, Jack said they'll handle that too.
"I always try to remind the guys how fortunate we are and don't let adversity bog you down," he said. "Understand that we are the fortunate few who get to live their dreams. Every kid growing up has dreams, and they start off sincerely trying to make those dreams come true. But everyone doesn't get that chance and we do and get paid pretty handsomely for it. So whatever it is that we're dealing with as a team, I try to be a vocal leader, a supporter and remind the guys about the big picture."
And if he happens to drop 20 along the way, well I guess they'll take that too.