Roberto Martinez’s side were cruising at the time of the winger’s departure after Michy Batshuayi had just made the scoreline 4-1.
But Hazard soured proceedings for the home fans by leaving the pitch with a limp just minutes later.
The Chelsea ace had been in sumptuous form before his exit.
However, the injury doesn’t appear to be serious from initial glances.
But with the World Cup underway on Thursday, Belgium fans will be sweating over the fitness of their star man.
Earlier in the match team-mate Dries Mertens also came off with an apparent knock.
The Napoli star was seen getting his hamstrings iced on the sidelines.
Speaking after the match, Romelu Lukaku reassured fans over the severity of the injury.
“He took a direct hit, as often,” he said.
“He came out as a precaution.”
After Hazard’s departure, a host of Chelsea and Belgium fans took to Twitter to discuss the apparent injury.
One wrote: “@hazardeden10 Are you okay? I hope you are fine!
While another said: “Belgium without Eden Hazard are basically Macedonia.”
And one said: “@hazardeden10 limps off with a knock. Substitution looked like a precaution though!!”
But one England fan certainly saw the positive side of the injury, writing: “Eden Hazard limps off injured for Belgium against Costa Rica. England to win the group confirmed.”
Belgium’s first game is against Group G minnows Panama next Monday.
Martinez will certainly be hoping the country’s poster boy is back in action before then.