LONDON (AP) -- Andy Murray won his first match since becoming a father as defending champion Britain and Japan tied 1-1 on the first day of their Davis Cup first-round match on Friday, while Novak Djokovic provided the point for Serbia, which is also 1-1 against Kazakhstan.
Murray hadn't played since losing to Djokovic in the Australian Open final on Jan. 31. His wife, Kim, gave birth to Sophia on Feb. 7.
''It has been tough the last few days being away from her for the first time, but it had to happen at some stage,'' Murray said.
Eight World Group matches are being played this weekend with the winners advancing to quarterfinals in July. Losers face World Group playoffs in September.
Playing his first match in nearly five weeks, Murray beat Taro Daniel 6-1, 6-3, 6-1 to successfully launch Britain's defense of the cup on an indoor court in Birmingham.
Murray and Kei Nishikori both won their 12th straight match in the Davis Cup though Nishikori had it much tougher in the second singles match before finally putting away 157th-ranked Dan Evans 6-3, 7-5, 7-6 (3).
Top-ranked Djokovic won the first point for Serbia by defeating Aleksandr Nedovyesov 6-1, 6-2, 6-3 before Mikhail Kukushkin beat Viktor Troicki 7-5, 6-2, 6-4 as Kazakhstan tied the 2010 champion 1-1.
Djokovic, who overcame eye infections to play and then seemed bothered by a sore shoulder, faced only one break point - in the third set.
''I lost some of the momentum in the third set, but it was enough to win the match,'' Djokovic said.
Djokovic and Nenad Zimonjic are slated to play in Saturday's doubles against Andrey Golubev and Nedovyesov.
Also Friday, Australian Bernard Tomic defeated American Jack Sock 7-6 (2), 6-3, 3-6, 6-4 to level their match 1-1. Earlier, John Isner gave the U.S. the lead with a 7-6 (2), 6-2, 6-2 win over Sam Groth on grass at Kooyong, the former home of the Australian Open.
Belgium leveled with Croatia at 1-1 after David Goffin defeated Borna Coric 6-3, 6-2, 2-6, 3-6, 6-3. Former U.S. Open champion Marin Cilic had given Croatia a 1-0 lead with a 7-5, 6-3, 7-5 win over Kimmer Coppejans.
Tomas Berdych defeated Alexander Zverev in a five-set encounter to draw the Czech Republic level with Germany at 1-1. Seventh-ranked Berdych prevailed 7-6 (6), 1-6, 4-6, 7-6 (5), 6-4 over the 18-year-old Zverev, who was making his Davis Cup debut. Earlier, Philipp Kohlschreiber defeated Lukas Rosol 3-6, 6-3, 6-4, 2-6, 6-3.
Gilles Simon overcame a sloppy start to beat Vasek Pospisil in straight sets and give France a 2-0 lead over Canada with Yannick Noah as France's new captain. Simon trailed 5-0 in the opening set before rallying past Pospisil 7-5, 6-3, 6-3. Gael Monfils eased past Frank Dancevic 6-3, 6-1, 6-3.
Paolo Lorenzi let slip a two-set lead and was forced to save three match points before beating Marco Chiudinelli to put Italy ahead against Switzerland, which is missing Roger Federer and Stan Wawrinka. Lorenzi won 7-6 (14), 6-3, 4-6, 5-7, 7-5 in a match which featured the longest tiebreaker in World Group history. Italy made it 2-0 when Andreas Seppi beat Henri Laaksonen 7-5, 7-6 (4), 3-6, 6-3.
Argentina leads Poland 2-0 in Gdansk as Guido Pella beat Michal Przysiezny 6-1, 6-4, 7-6 (5) and Leonardo Mayer defeated Hubert Hurkacz 6-2, 7-6 (3), 6-2.