DENVER—A woman celebrating her 69th birthday at the Colorado Rockies’ home opener Monday sustained a concussion when she was struck in the head by a foul ball off the bat of Michael Cuddyer in the fourth inning.

Judith Reese was treated at Denver health and released.

“I want to thank the fans, the paramedics and the community for their instant support,” Reese said, according to a news release from the hospital.

The game was briefly delayed in the top of the fifth inning while medical personnel attended to Reese, who was eventually carted off through the left-field tunnel.

Kara Jackson, a registered nurse from Broomfield, Colo., was sitting a few rows behind Reese when the incident occurred. Jackson said she held Reese’s head until paramedics arrived.

“The ball came too fast and nobody could respond,” Jackson explained. “It was flat; it wasn’t a fly ball.”

Reese was sitting near the railing just down from the third base dugout when Cuddyer pulled a ball into that area. Nearby patrons quickly motioned for the medical staff.

Cuddyer was shaken by the fan’s injury.

“I saw the ball off my bat, saw the stands part ways and boom—saw it hit the head,” said Cuddyer, who was making his Rockies debut at home. “I hope (she) is all right and everything is well. It’s tough. That’s the scary part of this.”