LONDON (AP) — Kobe Bryant’s barely broken a sweat. LeBron James hasn’t scored in double figures, and U.S. coach Mike Krzyzewski has swapped lineups like he’s trading Olympic pins.

After two games of the men’s tournament, America’s superteam has started slowly and showed some real vulnerability.

Maybe the world has a chance after all.

Maybe not.

Getting a jump start from its second unit after a less-than-inspiring first half by the starters, the U.S. turned on the burners after halftime and rolled to a 110-63 win over Tunisia on Tuesday night to improve to 2-0 in preliminary play — just as expected.

Carmelo Anthony and Kevin Love scored 16 points apiece and Kevin Durant added 13 for the Americans, who led by only 13 at halftime before outscoring Tunisia (0-2) 64-30 in a second half that became another highlight loop of alley-oop lobs, dunks and crowd-pleasing passes.

Krzyzewski began the second half with his reserves and Anthony, Love, Deron Williams, Russell Westbrook and Andre Iguodala responded with a 21-3 run that made it 67-36 and seemed to satisfy their coach, who didn’t look all that happy with his team’s effort when he left the floor at halftime.

“We told him, don’t get worried,” Anthony said. “We’re all right.”

But the Americans, who will face Nigeria on Thursday, haven’t exactly hit their stride.

Bryant has been in early foul trouble both games and played just 21 minutes, about the same as 19-year-old Anthony Davis, who dunked his way to 12 points against Tunisia. The U.S. has also shown a tendency to rely too much on jump shots and didn’t defend the perimeter well against Tunisia, which knocked down nine 3s.

It’s tough to criticize a team winning by 37 points per game, but the U.S. team, heavily favored to win its second straight gold medal, has displayed enough flaws to keep Spain, Argentina and Brazil dreaming of Olympic glory.

“This isn’t a sprint,” said Krzyzewski, who canceled Wednesday’s practice 11 hours before Tuesday’s opening tip. “It’s a longer race and there’s a lot of things that have to be done before the medal round. I know people go quarter by quarter, minute by minute, that’s not the way you develop a team.

“What did we get accomplished tonight? We won by almost 50 points against a team that really wanted to play hard against us.”

The Americans had to work much harder than expected to make this one look easy.

They were only ahead by five points late in the first half, launching 3-pointers when they couldn’t be stopped inside.

The second unit simply appeared to compete much harder, with Williams even playing one defensive possession with one shoe after the other fell off. Love briefly had to come out after banging knees, but was able to return later.

“It’s a different game to get ready for and I thought as a team overall we were ready, but it took our bench to get us going defensively,” Krzyzewski said.

Makram Ben Romdhane scored 22 to lead Tunisia, which lost its opener to Nigeria but had moments where it went toe to toe with the world’s top team.

“They could have absolutely have taken us to the cleaners but Coach K’s discipline made sure that didn’t happen,” Tunisia coach Adel Tlatli said through an interpreter.

The Americans had played nothing but top-level opposition of late, beating Argentina and Spain in their final two exhibition games before opening with a 98-71 victory over France. They played like they expected a little breather so they could concern themselves mostly with adjusting to the prefabricated arena and FIBA officials, who call a different game than NBA refs.

Tunisia wasn’t intimidated the way teams have been in the past against the U.S.

“It’s a dream for us to see these kinds of players, but now we play with them,” Ben Romdhane said.

The Americans missed all eight 3-pointers in the first, even worse than their 0-for-6 start Sunday, before Anthony nailed one to open the second quarter. Westbrook followed with a jumper for a 26-15 lead, and the expected U.S. blowout seemed under way.

Instead, Marouan Kechrid made consecutive 3s a couple of minutes later that brought Tunisia within six points, and he made another one with about 3½ minutes left, pumping his fist back toward his bench after cutting the U.S. lead to 35-30.

Only then did the Americans finally get control, rattling off 11 straight points, with James’ behind-the-back pass to Durant for a dunk making it 46-30.

With tough exhibition games before arriving in England, the U.S. team may need a break and Krzyzewski is giving them a day to decompress.

It may be their last break.

“We might go to some events tomorrow,” Anthony said. “We’ve been going non-stop and put a lot of work in.”

The toughest is still ahead.

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AP Sports Writer Brian Mahoney contributed to this report.

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