Belgium coach Marc Wilmots praised his team's "mental strength" as they came from behind to beat Algeria 2-1 in their World Cup opener.
The Red Devils trailed the Vahid Halilhodzic's side after Jan Vertonghen dragged down Sofiane Feghouli for a first-half penalty, which the midfielder duly converted.
Wilmots' decision to make all three changes available to him by the 65th minute paid dividends, with substitutes Marouane Fellaini and Dries Mertens netting the goals to complete the comeback.
"It was a difficult match," HLN.be reported him as saying. "We made a very little mistake, but at World Cups they are punished.
"During the first half, we had 67 percent of the possession but did not concede a chance -- I don't consider the penalty to be one."
After a lacklustre start, the coach maintained that the three points "are the most important thing" and that they would seek to build on their momentum in Group H.
"In the second half, this young team showed mental strength," he added. "The players from the bench made the difference."
After clinically finishing Eden Hazard's 80th-minute pass, Mertens admitted that while he was disappointed to miss out on a starting role, scoring the winning goal was the perfect reward.
"That is up to the coach and have to accept it, even though it was tough for me," he said. "Eventually I got the goal and I am happy with that."
Kevin De Bruyne -- who played an influential role in both of Belgium's goals -- echoed his coach's assertions over Algeria's strength, stating that his team must not allow the pre-tournament hype to distract them.
"The first half was very difficult," he said. "Algeria played with good organisation. It was a very good team performance in the second half.
"I know there a lot of expectations. For me, we have to take it game-by-game. Every game is different.
"I just want to prepare for Russia. We don't have to look to South Korea and the next round. We can't think too much ahead."