Updated

ANAHEIM (Reuters) - Los Angeles Angels slugger Kendry Morales belted a 10th-inning walk-off grand slam homer to secure a 5-1 win over the Seattle Mariners on Saturday, before his ecstasy turned to agony when he was injured celebrating the hit.

Morales took in the cheers of the home fans as he rounded the bases following the blast but fractured his lower left leg when he jumped on home plate as his team mates gathered to congratulate him.

Trainers tended to the 26-year-old Cuban for approximately 10 minutes while a stunned crowd looked on, before the first baseman was carted off the field.

Morales is scheduled to have surgery on Sunday and has been placed on the 15-day disabled list.

"In the exuberance of celebrating, he twisted his ankle," Angels manager Mike Scioscia told reporters. "It will change the way we celebrate. I know it's happened before. Unfortunately, it happened to us."

Morales' absence will be a blow for the Angels as he leads the team in batting average (.290), home runs (11), total bases (94) and RBIs (39) this season.

(Reporting by Mike Mouat in Windsor, Ontario; Editing by John O'Brien)