Rafael Nadal suffered his first defeat of the year in his 21st match, losing in straight sets to Taylor Fritz in the final at Indian Wells.
Nadal, 35, appeared out of sorts and quickly found himself 4-0 down before leaving the court for treatment.
He looked more comfortable on his return but struggled to break down a determined Fritz who won 6-3 7-6 (7-5).
"This is one of those childhood dreams you never even think will come true," said 24-year-old Fritz.
He saved two break points at 5-5 in the second set before winning a tie-break to secure his first Masters 1000 victory.