Joel Campbell was injured by a tackle while playing against Espanyol not long after returning from a knee injury.
According to La Prensa Libre, the winger was injured by a tackle from Espanyol midfielder Papa Diop.
With Betis trailing thanks to a goal from Gerard Moreno, Campbell came on as a 76th minute substitute to help turn things around.
He and Betis were unsuccessful, and their night seemingly got worse when a heavy challenge from Diop in the 93rd left Campbell requiring treatment after the final whistle was blown.
The extent of the injury is unknown at this stage. However, Betis manager Quique Setian seemed optimistic about it.
“He has pain. He received a very strong blow and we don’t know what it is, but he could walk, so let’s hope it’s nothing,” he said.
Campbell joined Real Betis on loan for the second time in his career in the summer.
He was in the process of regaining full match fitness after sitting out pre-season with a knee injury sustained during the Gold Cup.
He made a positive impact at Betis when he got a goal and an assist off the bench in a 6-3 defeat to Valencia.
This latest injury scare could rule him out of Costa Rica’s upcoming friendlies against Spain and Hungary.
Campbell has made three appearances for Betis so far this season. Two have come from the subs bench, while the other was a start in a 2-0 win over Deportivo Alaves.