Rajeev Ram came through a tightly contested three-set encounter with Ivo Karlovic to win the Hall of Fame Tennis Championships.

Ram, who won his first ATP singles title at the grass-court tournament in Newport, Rhode Island six years ago, won his second by beating a player ranked 137 places above him in Karlovic 7-6 (7-5) 5-7 7-6 (7-2).

Both players were solid on serve throughout the first set, with Karlovic the only player to face a break point, which he saved before losing the subsequent tie-break by sending a backhand volley into the net.

But Karlovic answered in the second set by breaking Ram in the 11th game, before holding to love to force a decider.

Normal service was resumed as the third was sent to another tie-break and it was Ram who prevailed again, sealing a win that will take him from 161 to 86 in the world rankings and earn the American direct entry into the US Open.

Ram said: "I'm in a little bit of shock here, I can't put into words what this means. At the beginning of the week I was just happy to be in the tournament.

"That's a year changer, I can't wait for the summer hard-court season. It's probably where I play my best."