France are many people's favourites to win Euro 2020.
The World Cup winners have so much talent in their 26-man squad.
But there may be problems between two of their key players going into the tournament.
The Chelsea striker called out his teammate for not passing to him after their convincing win.
"Sometimes you make the runs and ball is not arriving. Perhaps we could have found each other better, there it is," he said, per the Daily Mail.
Mbappe appears to have not reacted very well to those comments.
Per L'Equipe, he felt attacked and wanted to call a press conference to fire back at Giroud.
But Didier Deschamps has refused to let him do so and has told him to concentrate on France's Euro 2020 opener against Germany.
With the two not in each other's good books, Mbappe's reaction to Giroud's first goal against Bulgaria looks interesting now.
Many of France's teammates, including Benjamin Pavard and Raphael Varane, were ecstatic when Giroud hit the back of the net.
But not Mbappe. The PSG star showed absolutely no reaction at all as he turned around and trudged back to the half-way line.
It's important to not read too much into Mbappe's reaction given it was just a friendly.
But he clearly wasn't overjoyed when Giroud hit the back of the net.
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In fact, it almost looked as if he didn't care much at all.
It will be interesting to see how this story develops. It's certainly not ideal for France if two of their players have indeed fallen out going into a major tournament.