Copa America holders Argentina made a winning start at the 2024 tournament as Julian Alvarez and Lautaro Martinez scored in a 2-0 win over Canada.
The 2022 World Cup winners did not have things all their own way against Jesse Marsch's competition debutants, who missed a couple of glaring chances through Alphonso Davies and Jonathan David.
But on the day he became the Copa's outright leading appearance-maker, Lionel Messi was the catalyst for both goals, splitting the Canada defence in the build-up to Alvarez's opener then assisting Martinez's late clincher.
The Inter Miami star missed two great chances to get on the scoresheet himself, but it was of no consequence as Lionel Scaloni's men started with three points.
They take on Chile, who beat them in the 2015 and 2016 finals, in their second match on Tuesday, while Canada will look to bounce back versus Peru.
Canada refused to sit in and their approach left them open at the back early on. Leandro Paredes curled a 25-yard effort narrowly over the top, then Alvarez saw his shot smothered by Maxime Crepeau after a lightning break took him clean through on goal.
Despite Argentina dominating possession, Canada should have gone ahead on the stroke of half-time, Emiliano Martinez making a reflex save to deny Stephen Eustaquio before Davies miscued on the follow-up.
They were made to regret that miss four minutes into the second half. Messi's pinpoint throughball found Alexis Mac Allister, and though the midfielder was wiped out by Crepeau, Alvarez was on hand to convert into an empty net.
Messi should have made it 2-0 after 65 minutes, but he saw an angled drive parried by Crepeau before Derek Cornelius made a fine block to deny him on the rebound.
Canada continued to offer a threat at the other end, though, with David heading over after being found totally unmarked by Jacob Shaffelburg's cross.
Messi missed another chance when his dinked attempt rolled agonisingly wide, but he did manage an assist as Argentina made the result safe two minutes from time.
His delicate pass sent Martinez clear, and the substitute slotted a composed finish between the legs of Crepeau.
Assist for Messi on landmark appearance
Messi made a piece of Copa America history on Thursday, his 35th appearance in CONMEBOL's flagship tournament pulling him clear of Chile great Sergio Livingstone for the most games played at the competition outright.
The eight-time Ballon d'Or winner failed to mark the occasion with a goal, misfiring from a game-high six shots worth 0.69 expected goals (xG).
However, he did cap his outing with an assist for Martinez's late second, taking him to 30 goal involvements at the tournament overall (13 goals, 17 assists).
Messi still has plenty of gears to go through, and that should strike fear into Argentina's upcoming opponents.
Encouragement for Canada, but no points
Canada became the 20th different nation to participate in the Copa America, and the eighth different CONCACAF team after Costa Rica, Haiti, Honduras, Jamaica, Mexico, Panama and the United States.
As was the case at the 2022 World Cup, they played some high-octane football but were not rewarded with a positive result.
At half-time, Marsch's team had matched Argentina's tally of seven shots, the most any team have attempted in a first half against the Albiceleste since Uruguay managed eight in November 2021. Their 0.73 xG, meanwhile, topped the world champions' 0.56 at that stage.
Alvarez's opener came as a dagger blow and they were unable to sustain their high-intensity approach for the full 90 minutes, but there were positives to take.
Ahead of Thursday's opener, the Opta supercomputer gave Canada just a 27 per cent chance of escaping Group A. While the result will have done nothing to boost those hopes, their display should offer encouragement ahead of meetings with Peru and Chile.