Anderson made 46 saves in his first start after a seven-game absence, good for a 5-3 win against the Chicago Blackhawks on Friday.
Chicago scored two goals later in the period before Ottawa center Kyle Turris scored a power-play goal 6:00 into the third to put the Senators up 4-2. Clarke MacArthur scored at 10:54 to increase the lead to 5-2 and tie Bobby Ryan for the Senators' lead in goals with his 23rd. MacArthur had a goal and two assists.
"The bottom line is, we got two points and we found a way to win, and that's all that really matters," said Anderson, who sustained an upper-body injury March 10. "We played pretty solid, and for the most part we did what it took to get the job done."
Blackhawks defenseman Brent Seabrook scored a shorthanded goal with 3:00 left.
Patrick Sharp scored a power-play goal midway through the second period to draw Chicago within 3-1 before Anderson made a sensational left-pad save on Andrew Shaw's scoring chance from the edge of the crease.
Former Senators forward Marian Hossa scored with 41 seconds left in the second to draw the Blackhawks within 3-2.
"We had the puck a lot," Sharp said. "We created some scoring chances, we did some good things with it at different times in the game, but a few mistakes ended up in the back of our net, and they've got some skilled players over there that take advantage of those mistakes and they put it in the back of the net."
Goaltender Antti Raanta made 24 saves in his first start in six games for the Blackhawks, who on Thursday were shut out for the second time in three games, a 3-0 loss to the Boston Bruins in Chicago's first game at TD Garden since it won the Stanley Cup there last spring.
The Blackhawks, who lost for the third time in four games, would have clinched a Stanley Cup Playoff spot with a win or a point from an overtime or shootout loss. They also could have clinched if the Dallas Stars lost to the Nashville Predators, but the Stars won 7-3.
"I didn't like our game tonight," Blackhawks coach Joel Quenneville said. "We had a good start, and obviously giving up a shorthanded goal right off the bat, they got some momentum off it and they played well, and they got [goals] late in the period and early in the second, and we were down 3-0.
"And then we played a perfect second period and tried to claw our way back into it, but way too many quality chances against. I know we generated a ton offensively, but I didn't like what we gave up defensively more than anything tonight."
Chicago (42-18-15), which has seven games remaining, is in second place in the Central Division with 99 points, eight behind the first-place St. Louis Blues and one ahead of the Colorado Avalanche. St. Louis and Colorado each have two games in hand.
"These are big games for everyone that we play against, including ourselves," Blackhawks captain Jonathan Toews said. "The time is now to play our best hockey, so if we can kind of think of it in the way where we're going to battle through this, and it's not fun and it's kind of tough to play hockey when things aren't clicking for you, but once we do get on the same page and we do get working I'm sure we'll be re-energized as a team and things will start going our way the way we're used to when we're working well as a team."
The Senators won for the second time in three games (2-0-1) following a four-game losing streak. Ottawa (30-29-14) moved past the Carolina Hurricanes into 12th place in the Eastern Conference with 74 points.
"You cannot focus on what could be or what should be, et cetera, et cetera, you have to just stay in the moment and take it one game at a time," Anderson said. "Anything can happen, but if we think, 'Oh yeah, we can win the next eight and get ourselves in,' you're just defeating yourself. You have to go one game at a time, and if we continue to win, anything can happen. You just don't know and you have to play it out."
Condra opened the scoring with a shorthanded goal at 9:25 of the first period after MacArthur was sent off for goaltender interference when he fell on top of Raanta.
Raanta later injured his right leg when he fell awkwardly at 12:50 of the first. Corey Crawford got ready to come in, was on the ice to stretch, but Raanta remained in the game.
Crawford had appeared in 27 of Chicago's previous 32 games since missing 10 from Dec. 10-30 because of a groin injury.
Ceci made it 2-0 with his third goal of the season with 30 seconds left in the first period.
"I thought we competed better tonight," MacArthur said. "We had a little lapse in the second, but you're playing Chicago, they're going to make a push and we were able to make plays in the third and not clam up. I thought we kept the puck moving ahead and did a better job in the third."
Shaw was given a major penalty for spearing Zack Smith, a game misconduct and a roughing minor at 14:33 of the third. Smith got minors for slashing and roughing.
Blackhawks left wing Matt Carey made his NHL debut. Carey signed with the Blackhawks as a free agent after his freshman season at St. Lawrence University.
Ryan had season-ending surgery Thursday in Montreal. The forward, who had 23 goals and 25 assists for 48 points in 70 games, missed Ottawa's previous two games because of a sports hernia injury he aggravated in a 3-1 road loss to the Stars on Saturday.
|SHG - Erik Condra (6) ASST: Zack Smith (8)|
1 - 0 OTT
|Cody Ceci (3) ASST: Clarke MacArthur (28), Mark Stone (3)|
2 - 0 OTT
|Milan Michalek (14) ASST: Jason Spezza (41), Ales Hemsky (24)|
3 - 0 OTT
|PPG - Patrick Sharp (31) ASST: Jonathan Toews (40), Antti Raanta (1)|
3 - 1 OTT
|Marian Hossa (27) ASST: NONE|
3 - 2 OTT
|PPG - Kyle Turris (23) ASST: Clarke MacArthur (29), Patrick Wiercioch (15)|
4 - 2 OTT
|Clarke MacArthur (23) ASST: Mark Stone (4)|
5 - 2 OTT
|SHG - Brent Seabrook (7) ASST: Michal Handzus (11), Peter Regin (7)|
5 - 3 OTT
|Clarke MacArthur Interference on goalkeeper against Antti Raanta|
|Chris Neil Fighting (maj) against Brandon Bollig|
|Brandon Bollig Fighting (maj) against Chris Neil|
|Chris Neil Interference on goalkeeper against Antti Raanta|
|Jared Cowen Hi-sticking against Patrick Sharp|
|Matt Carey Delay Gm - Face-off Violation|
|Jared Cowen Interference against Ben Smith|
|Eric Gryba Slashing against Marian Hossa|
|Andrew Shaw Roughing against Zack Smith|
|Zack Smith Slashing against Andrew Shaw|
|Andrew Shaw Spearing (maj) against Zack Smith|
|Zack Smith Roughing against Andrew Shaw|
|Andrew Shaw Game misconduct against Zack Smith|