Courtois and Hazard are currently on their pre-season tour with Chelsea in north America as Jose Mourinho’s men prepare for their Premier League title defence.
The national holiday is celebrated on the 21 July every year and Courtois used social media to send his best wishes to his compatriots.
Courtois uploaded the photo above onto his Instagram account and wrote: “Happy National Day to my compatriots!! #belgium @hazardeden_10”
Courtois, 23, made 32 appearances for Chelsea last season as they won their fourth Premier League title, as well as the League Cup.
Hazard was in top form for the west London club as he helped Mourinho’s men win the Premier League and League Cup in the Portuguese coach’s second season back in charge.
Chelsea, who also won the League Cup last season, kick off their Premier League title defence with a home clash against Swansea City on the opening day of the campaign.
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