One good quarter is not enough to beat the reigning Olympic champion.
The United States lost 10-7 to Italy in its opening game of the water polo tournament Saturday.
After two quarters, the teams were tied 4-4. But Italy, which is also the world and European champion, outscored the Americans 6-3 in the last two periods and cruised home.
Despite the loss, the Americans remain in medal contention. The preliminary round is played under a round-robin format, with four teams from each of the two six-nation groups advancing to the quarterfinals.
"They couldn't have played worse. We can't allow goals from 2 meters," U.S. coach Rich Corso said. "Let's forget it and move on."
The U.S. team can redeem itself today against Greece.
The Italians took the lead with 4:19 left in the first quarter when Alberto Ghibellini slipped the ball under the arm of American goalkeeper Chris Duplanty.
Chris Humbert, the 6-foot-7 leading scorer for the U.S. team, tied it less than a minute later with a power-play goal from long range. But then the host nation gave up three goals in a row.
In earlier games, a dramatic lob by Tamas Kasas with eight seconds left gave Hungary an 8-7 victory over Russia.
In the first match of the competition, Yugoslavia, a three-time champion when it still included six republics, returned to Olympic water polo by winning 11-8 over the Netherlands. Yugoslavia now consists only of Serbia and Montenegro.
Croatia, the second powerful team to emerge from the breakup of old Yugoslavia, also began with a victory, beating Greece 8-5 behind three goals by Dubravko Simenc.
Spain, silver medalist in Barcelona, cruised to a 9-3 victory over Germany, helped by good goalkeeping from Jesus Rollan and two goals apiece from Salvador Gomez and Miguel Oca.
Andrei Kovalenko scored his fourth goal with 16 seconds left to cap a rally by Ukraine from a three-goal deficit in a 6-6 draw with Romania.