WFC - Chelsea (Lampard and Ivanovic) with the Seahawks

WFC: Chelsea FC stars get a taste of the "other football"

RENTON, Wash. — Boys will be boys, after all.

On a warm morning at the Virginia Mason Athletic Center, just south of Seattle, 2011-12 UEFA Champions League winners Chelsea FC were put through their paces in training under the bright sunshine. Head coach Roberto Di Matteo looked on as Michael Essien, Frank Lampard, David Luiz & Co. worked up a decent sweat in preparation for Wednesday night's Herbalife World Football Challenge opener against the Sounders (9:30 pm ET; ESPN2).

Then the final whistle blew and the fun really began.

The Blues stars joined up with several members of the NFL's Seattle Seahawks for a jersey exchange and an impromptu game of ... well, let's call it "Calvinball." It wasn't quite American football, and not quite soccer, but it didn't have to be. Sometimes it's just nice to run around outside.

"It's great to have the possibility to try to play American football," said Chelsea's Branislav Ivanovic, a self-styled wide receiver for the day. "A lot of our guys follow this [the NFL] during the season, and to meet the guys from the Seahawks, it's a great, great opportunity for us."

Lampard kicked the horseplay off, immediately running a route (and surprising this reporter, for one, by making a nice leaping catch) as Seahawks backup Russell Wilson choreographed the action. Several other Seattle players were working on their footskills — turns out linebacker Malcolm Smith can juggle fairly well — before Ivanovic stole the show by deciding to go long. Repeatedly.

And whatever he lacked in training, he made up for in enthusiasm.

"It's great," the defender said. "What they are doing [in training], all these things when you see the guys, it's really impressive for us and a great experience. We saw a couple of guys doing the stuff in the gym, and looking so impressive. Of course they are so strong and they have to be ready for the games, but they are looking really impressive, I'll say it again."

But it's not time for a career switch just yet.

"I'll stick with soccer," Ivanovic said with a laugh, "cause the guys are massive! Very strong!"

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