Lionel Messi forced off through injury as Miami put four past Toronto
Messi returned to the starting line-up after skipping Saturday's 5-2 defeat at Atlanta due to muscle fatigue but he had to leave the field in the 38th minute, looking uncomfortable.
His former Barcelona team-mate, Spaniard Jordi Alba who had also sat out the trip to Atlanta, had limped off three minutes earlier in the game.
"They had to come out, we will evaluate them in the coming days," Miami coach Gerardo Martino told broadcasters Apple TV at the interval.
Despite the blow of losing their star and one of their most influential players, Miami swept aside the Eastern Conference's bottom club with some ease.
Facundo Farias opened the scoring on the stroke of half-time with a blistering volley after Toronto keeper Tomas Romero had meekly palmed out a Noah Allen cross.
Substitute Robert Taylor then made it 2-0 in the 54th minute with an outstanding individual strike, dribbling across the box from the left before unleashing a sharply angled drive back into the bottom corner.
Taylor then turned provider, releasing another substitute Benjamin Cremaschi who fired through the legs of Romero to make it 3-0.
Finnish international Taylor completed his impactful performance with the fourth, bringing down a floated pass over the top from Farias and blasting home from close range.
The performance of Taylor, Cremaschi and other substitutes will give Miami confidence that they can maintain a push towards the post-season, even if Messi and Alba may need more time to get back to fitness.
"It shows guys are willing to step up, shows the depth we have on our team, and the collective mentality we approach each game with," said goalkeeper Drake Callender.
"Whether we have our original starting eleven or whether we have players who come off the bench, I think it shows that if you get an opportunity to play on this team, you’re prepared for it," he added.
Miami, who travel to Orlando on Sunday, move up to 13th in the Eastern Conference and are now just five points off Wayne Rooney's D.C. United who occupy ninth spot, the final playoff position. Miami have two games in hand.
D.C United were held to a 1-1 draw at home to Atlanta while other results were also favourable for Miami.
Charlotte, who Miami have to play twice, are now just two points ahead of the Florida side after they let a two-goal lead slip in a 2-2 draw at home to Philadelphia, conceding a stoppage time penalty which was converted by Daniel Gazdag.
The Columbus Crew beat the Chicago Fire 3-0 with Colombian Cucho Hernandez scoring all three inside 23 minutes - the second fastest hattrick from the start in MLS history.
Tenth placed New York City kept their playoff hopes alive with a 2-0 win at home to second placed Orlando City.
Eastern Conference leaders Cincinnati needed a goal deep in stoppage time from Argentina Luciano Acosta to earn a point at eighth placed Montreal.
