Top-seeded and two-time champion John Isner was upset in the opening round of the Hall of Fame Tennis Championships by Rajeev Ram 6-7 (5), 6-3, 7-6 (8) on Tuesday.

The 18th-ranked Isner won the title on Newport's grass in 2011 and 2012.

The 161st-ranked Ram, who won the tournament in 2009, closed the match with a forehand winner after Isner slipped on the wet grass with a light rain falling.