Dubai, UAE - Croatian seeds split the difference on Monday's opening day at the Barclays Championships, with Marin Cilic fighting back as Ivo Karlovic crashed out to a qualifier.

Cilic, seeded fifth, met up with Serbian Janko Tipsarevic and handed his familiar rival a third defeat over seven weeks in their series, 2-6, 7-6 (7-3), 6-4.

Swiss qualifier Marco Chiudinelli began putting in a bid for a place on next week's Swiss Davis Cup team to face the US.

The number 44 who won a match in Johannesburg this month, rallied past the big-serving game of Karlovic, 7-6 (7-4), 4-6, 7-6 (9-7) despite more than 20 aces from the tallest man in the sport.

Cilic said that he was pleased to get back into his contest with Tipsarevic after a slow start as he lost his first two serves.

"I saved two break points in the first game of the second set and that got me going," said the 19th-ranked winner of the Chennai title last month.

"I had chances in the tiebreaker and in the third set I was able to close it out."

Cilic still had to work after his opponent saved four match points on serve in the penultimate game, but the Croatian brought the contest to a swift end after a lengthy two hours 20 minutes with a concluding ace one game later.

"Our matches have all been struggles," said Cilic, now 14-1 on the season. "This one was more of the same.

"I'm playing more consistently this season and I'm stronger," the 20-year-old said of his improved form after training in San Remo, Italy, with his longtime mentor Bob Brett.

Second seed Andy Murray was opening later in the first round against Sergiy Stakhovsky in a preview of next week's Davis Cup zonal tie against the Ukraine. (dpa)