CLEVELAND -- The Cleveland Cavaliers added point guard Jarrett Jack in free agency during the offseason, and his veteran leadership could not have emerged at a better time than now.

The Cavaliers lost their leading scorer, point guard Kyrie Irving, to a strained tendon in her left biceps with the team in the midst of a playoff race.

Despite a four-game losing streak following Irving's injury, Jack has led the Cavaliers to within three games of the eighth and final playoff spot in the Eastern Conference after winning four of their last five outings.

"He's done a great job," Cavaliers forward Tristan Thompson said. "That's what point guards are supposed to do. That's what their role is to do. Jack has been doing it, and Kyrie's good at it too when he's healthy. We can't wait for him to come back, but it's an opportunity and Jack's making the best of it in leading us. He's an extension of Coach (Mike) Brown on the court, and that's his job."

Rookie guard Matthew Dellavedova added, "He's been really vocal and he's been playing great basketball. In that New York game, he took over, especially in the fourth quarter. He's been playing some great basketball lately."

During the stretch without Irving, Jack has led the team in scoring twice, including a double-double of 31 points and 10 assists in a 106-100 victory over the New York Knicks at Madison Square Garden, but according to Cavaliers coach Mike Brown, what has been most valuable to the team is Jack's leadership.

"Floor general, floor commander, floor chieftain, there's a lot of different things you could call him," Brown quipped after Sunday's 90-76 win over the Indiana Pacers, a game in which Jack totaled 11 points, six rebounds and nine assists without a turnover.

"He's been giving us a lot of what I told you in the huddle," Brown said. "That leadership on the floor, off the floor has been terrific, especially down the stretch in tight ball games. He's kept us composed offensively."

"There's been times, in the past, where we're in a situation, and if we're down, we rush ourselves or we're going too fast for the situation, time and score. We don't need to come down and jack up a three if we're down five with two minutes to go in the game.

"We can move the basketball, get a good shot and make sure we get it in flow with guys in position for a rebound, transition defense or whatever it may be. Jack has done a terrific job, no matter what the time and score is, of understanding, feeling the game and helping his teammates out."