Experience tells Chris Mason to be ready. Always be ready.

In the NHL, a goaltender can go from spectator to combatant in a moment’s notice. Fore the second time this season, Mason's moment has come.

A wrist injury will sideline Ondrej Pavelec, who has played 47 of 64 games, for an undetermined period of time and the weight of the Thrashers' playoff hopes has recently fallen on Mason’s stacked pads. With 18 games remaining in the regular season, the Thrashers entered Wednesday's schedule tied for 10th in the Eastern Conference, six points behind Carolina for the eighth and final playoff spot.

Pavelec was injured in the first period of Friday’s game against Florida. Mason came on in relief and stopped all 25 shots he faced, as well as four of six shootout attempts, while the Thrashers lost 2-1. He has allowed just four goals, one on a power play, in the two following games, an overtime win over Toronto and a loss to Montreal. Mason has stopped 67-of-71 shots (.944 save percentage) over the three games.

“He is probably one of the least guys that I worry about because of his experience. He’s seen it all, done it all at this point of his career and because of his makeup,” Thrashers goaltending consultant Clint Malarchuk said. “He’s learned that you don’t get too high and you don’t get too low.”

Mason makes his third straight start Thursday against Ottawa and this is not new territory for him. He was called on when Pavelec lost consciousness and collapsed only minutes into the season opener. He played 10 of the next 11 games until Pavelec returned full time and then watched as Pavelec went on one of the hottest streaks in franchise history.

It was just the start of an up-and-down season for Mason.

“Playing wise, it’s been tough,” he said of his first season in Atlanta. “I played a lot of games at the start and played fairly well. Then I had a couple of bad games and Pavs was just unbelievable. That’s the way it goes. You open the door and he just played amazingly. During that stretch, he was the best goalie in the NHL.”

Pavelec played 27 of the next 34 games. Mason finally got a start on Jan. 15 and lasted just eight minutes before he sprained the MCL in his right knee. Back to the bench, he missed another 12 straight games until he returned in a 5-3 loss at Edmonton on Feb. 19, an outing Mason said was not his best.

One game later, Pavelec was injured, summoning Mason right back into the middle of the playoff run. Mason, 34, said experience has helped him deal with the trials of the season.

“You have to understand [sitting while Pavelec was on a roll],” Mason said. “Had I been younger going through that, it would have been tougher. You always want to play but I have a better understanding of how the game works and what I have to do when I’m not playing. You have to be ready because you never know when you are going to get the chance again.

“Every year is so different. Every year you set ideals before the season but until you get going, you have no idea what to predict. Hockey-wise, it’s been up and down. But I understand the situation. Otherwise, I’ve had a great year here in Atlanta.”

Being in the middle of a push for the playoffs is also nothing new for Mason. He carried St. Louis into the playoffs in 2009 by starting the final 38 games of the season, accumulating a 24-8-6 record which included five shutouts. During the stretch he had a 2.08 goals-against average and a .924 save percentage.

“You definitely draw on the experience because any time you’ve done something before, you go back to that situation,” Mason said. “That’s what I’m doing. ... You never know what’s going to happen when a player gets hurt. Another player is in the lineup. I owe it to myself and my team to be ready.”