The 22-year-old rookie, who is making his 10th NHL start, made 24 saves in a 4-3 overtime win against the New York Islanders on March 9.
The win against the Islanders ended a six-game losing streak for the Maple Leafs, last in the League with 55 points.
Sparks used to work for Senators goaltender Craig Anderson at his goaltending school in Chicago. Anderson starts for Ottawa on Saturday.
"Consistency is a little easier to establish when you're playing more regularly," Sparks said. "It's an opportunity that I've been given and I want to do the most I can with it."
The Senators, who are seven points behind the Detroit Red Wings for the second wild card out of the Eastern Conference, lost 6-2 to the Florida Panthers on Thursday.
"We're coming in here every day trying to do the best we can do," captain Erik Karlsson said. "Last game, I didn't think we got that out of anyone. Unfortunately, that can happen. We're in a situation where we can't afford those types of games. That's why it's going to be so costly for us.
"I think we got in here today trying to be better, trying to keep our heads high. We're not going to have any kind of negativity going around this room no matter what is going on. We put ourselves in this situation and we're going to have to take ourselves out of his situation. We're going to have to deal with our own mess."
Ottawa, which is 4-4-2 in the past 10 games, has allowed a League-leading 218 goals this season and has a minus-20 goal differential.
"We've done what we've done to ourselves to be where we are today," Karlsson said. "There's a lot of reasons why we are where we are. We're trying every day to try and sort that out and figure out what we have to do to play better as a team and win more games. We've proven we can win as the team that we are and unfortunately we haven't got that done as of late. We're going to have to deal with the consequences."
The Senators have lost three games in a row and five or their past six (1-3-2).
Here are the projected lineups:
MAPLE LEAFS
Nikita Soshnikov - Nazem Kadri - Leo Komarov
Pierre-Alexander Parenteau - William Nylander - Zach Hyman
Colin Greening - Brooks Laich - Peter Holland
Milan Michalek - Ben Smith - Michael Grabner
Jake Gardiner - Morgan Rielly
Martin Marincin - Connor Carrick
Rinat Valiev - Frank Corrado
Garret Sparks
Jonathan Bernier
Injured: Stephane Robidas (knee), Joffrey Lupul (undisclosed), James van Riemsdyk (foot), Tyler Bozak (upper body), Byron Froese (hand), Matt Hunwick (sports hernia), Brad Boyes (shoulder), Viktor Loov (undisclosed)
Scratched: None
SENATORS
Mike Hoffman - Mika Zibanejad - Bobby Ryan
Zack Smith - Jean-Gabriel Pageau - Mark Stone
Ryan Dzingel - Scott Gomez - Alex Chiasson
Nicholas Paul - Curtis Lazar - Chris Neil
Marc Methot - Erik Karlsson
Dion Phaneuf - Cody Ceci
Michael Kostka - Chris Wideman
Craig Anderson
Andrew Hammond
Injured: Mark Borowiecki (knee), Kyle Turris (ankle), Chris Phillips (back), Clarke MacArthur (concussion)
Scratched: Matt Puempel, Patrick Wiercioch.
Status report: Valiev, 20, is expected to make his NHL debut. He was Toronto's third-round selection (No. 68) in the 2014 draft. He has three goals and 18 assists in 53 games with the Toronto Marlies of the American Hockey League this season. He will be the 11th rookie to play for the Maple Leafs this season.
Who's hot:Smith has five goals and three assists in his past seven games. … Stone has a goal and three assists in his past four games. … Hyman has two goals in his past two games.
