Michael Phelps of the US smiles after competing in the men's 200m freestyle semifinal at the 14th FINA World Championships in Shanghai July 25, 2011. [Photo/Agencies]

SHANGHAI - Michael Phelps is going after Germany's Paul Biedermann, and this time he's got help.

Having been handed "a pretty good beatdown" by Biedermann in the 200-meter freestyle two years ago in Rome, Phelps gets a long-awaited chance at revenge in the world championships Tuesday.

Biedermann trounced Phelps and took away his world record in Rome, where everyone was wearing the high-tech bodysuits that are now banned.

Phelps and Biedermann won't be going one-on-one, though. They'll be joined by what Phelps described as "a study field" in the night final at the Oriental Sports Center.

Yannick Agnel of France was the fastest qualifier in the semifinals, with Biedermann second, American Ryan Lochte third, Park Tae-hwan of South Korea fourth and Phelps fifth.

"It's going to be down to the last 50 (meters)," Phelps said. "There are some guys that have front-half speed and some guys that close extremely well. You can probably guarantee that it's going to be a tight group."

Lochte didn't swim the 200 freestyle in Rome, but he figures to be a major presence this time. "It's going to be definitely a dogfight," he said, noting that he and Phelps will swim next to each other.

"I'm going to kind of move over to the lane line and draft off him. Hopefully we can put something together and pull out a 1-2 race."

Biedermann predicted the final will be "big pressure."

After the semis, Phelps said he remained upbeat about his chances. "As long as I have a lane, that's all I need," said Phelps, who will swim in lane two. "I have my strategy that I want to do tomorrow. I tried to conserve as much as I could."