* United States, Finland start with easy wins
* Czechs earn hard-fought victory against Latvia
* Norway stun Sweden 5-4 in shootout (Adds Czech, Sweden results, quotes, details)
BRATISLAVA, April 30 (Reuters) - The young United States squad began their ice hockey world championship with a 5-1 victory over Austria on Saturday but holders Czech Republic had to work hard to beat a stubborn Latvia team 4-2.
Finland enjoyed a revenge victory against Denmark, also by 5-1, while Norway won 5-4 in overtime against Sweden.
Chris Kreider, drafted by the New York Rangers and named player of the match, celebrated his 20th birthday with the opening goal for the U.S. after 14 minutes. Blake Wheeler extended the lead to 2-0 four minutes later.
Austria failed to take advantage of a five-on-three power play in the second period but shot a contact goal one minute later as Marco Pewal punished the Americans' inability to convert several chances.
Yan Stastny, son of former NHL and Slovakian player Peter Stastny, took the U.S. to 3-1 in the 39th minute and strikes by Kevin Shattenkirk and Craig Smith in the third period finished off the Group C victory in the eastern Slovakian town of Kosice.
"We are satisfied; two more matches (in the group) are ahead of us and we have to play better in these next matches," Stastny told reporters.
The Czechs had to battle for their victory after twice going behind to a dangerous Latvia team in their Group D game.
Lauris Darzins stunned the Czechs in the 10th minute but Tomas Rolinek levelled the scores before the Latvians went ahead again in the second period through Roberts Bukarts.
Patrik Elias got the Czechs back into the match in the 32nd and assisted Martin Havlat who made it 3-2 in the 42nd before Roman Cervenka wrapped up the victory just before the hour.
In the other Group C game, Norway won 5-4 in overtime against a Sweden team that wasted the 3-1 lead built up by Loui Eriksson and two goals from Patrik Berglund in the first period.
Norway's Martin Roymark scored in the first period before Morten Ask and Marius Holtet found the net in the second to bring their team level at 3-3.
Eriksson put Sweden ahead again in the 50th minute but Anders Bastiansen secured a 4-4 draw, triggering a goal-free overtime and then a shootout in which Norway prevailed.
Jarkko Immonen put Finland ahead after 24 minutes against Denmark in the other Group D game on the second day of the championship.
Juhamatti Aaltonen, in the second period, and Antti Pihlstrom, Janne Niskala and Tuomo Ruutu in the third, completed Finland's revenge for an opening defeat by Denmark in last year's tournament in Germany.
(Reporting by Martin Santa; Editing by Clare Fallon and Ken Ferris; To query or comment on this story email sportsfeedback@thomsonreuters.com)