Andy Murray reached the second round of the Japan Open with a straight-sets victory over Ivo Karlovic in his first match since winning the US Open.
Karlovic entered the tournament as a lucky loser after Murray's scheduled first-round opponent Gael Monfils withdrew due to injury. Murray had won all four of his previous meetings with the giant Croatian, most recently in four sets at Wimbledon this summer, and was rarely troubled as he made it five from five with a 7-6 (9/7) 6-4 win.
The Scot failed to take any of his three break points in the first set but eventually prevailed in a tie-break.
The second set was progressing in a similarly serve-dominated manner until the 10th game, when Murray went up 0-40 to set up three match points. Karlovic saved two, the first with a second-serve ace, but Murray took the third to wrap up the win having not faced a single break point in the match.
He will face Lukas Lacko in the second round after the Slovakian hammered Spain's Albert Ramos 6-0 6-2. Meanwhile, Fifth seed Nicolas Almagro was a first-round casualty as Japan's Tatsuma Ito claimed a notable scalp to delight the home crowd.
The first set went to a tie-break after a final Ito service game which continued for almost 10 minutes after first reaching deuce. The home player had saved six break points up to that stage and made Almagro pay by taking the set in the breaker.
The second set also went the distance, with Ito repeating the dose to win 7-6 (7/4) 7-6 (7/5).
Fellow seed Milos Raonic and Kei Nishikori progressed safely through, though. A single break in each set was enough for sixth seed Raonic to power past Czech Radek Stepanek 6-4 6-4 while Nishikori, seeded eighth, won his all-Japanese clash with Go Soeda 4-6 6-2 6-3.
Raonic will face Tommy Robredo in the next round after the Spaniard beat Jarkko Nieminen 6-2 6-4, while Dmitry Tursunov saw off young Australian Bernard Tomic 6-4 7-5 to set up a match against Ito.
Marcos Baghdatis overcame Sergiy Stakhovsky in two tight sets, winning 7-6 (7/3) 7-5, Alejandro Falla beat Thomaz Bellucci 7-5 6-2, Jeremy Chardy eased past home wild card Yuichi Sugita 6-1 7-5 and Marco Chiudinelli beat Martin Klizan 7-6 (7/3) 6-2.