Britain's Jamie Murray and Australian John Peers suffered their first defeat at the ATP World Tour Finals in the second group match.
India's Rohan Bopanna and Florin Mergea of Romania won 6-3 7-6 (7-5) to secure the first semi-final place.
Murray and Peers won their opening round-robin match, so can still claim the second qualification spot.
They will take on American's Bob Bryan and Mike Bryan in their final group match at the O2 Arena on Thursday.
Peers dropped serve with a double fault in the first game and the fourth seeds could not convert any of the five break points as Bopanna and Mergea saw out the set.