Michael Phelps added another line to his Olympic legend on Tuesday -- with a little help from his friends.

Phelps anchored the United States to victory in the the men's 4x200m freestyle relay to claim the 19th Olympic medal of his career, eclipsing Soviet gymnast Larisa Latynina's record of 18.

After Phelps had matched Latynina with a silver medal in the 200m butterfly earlier in the night, team-mates Ryan Lochte, Conor Dwyer and Ricky Berens made sure Phelps' record-breaking medal was a gold one.

"I thanked those guys for helping me get to this moment," said Phelps, who was staked to a big lead by the first three swimmers and made it stand up against Yannick Agnel -- whose last-lap surge past Lochte had lifted France to victory in the 4x100m free relay.

"I told those guys I wanted a big lead in the last leg and they gave it to me," Phelps said. "I just wanted to hold on. I just wanted to thank them for allowing me to have this moment."

Lochte, the 200m free world champion who failed to medal in the individual 200m final won by Agnel in devastating style, put the US in charge with a confident lead-off leg of 1:45.15.

"People kept telling me I was better than that, to just put it behind me and move on," Lochte said of the support he had received after his fourth-placed finish in the 200m free final on Monday night.

"I woke up and I was back to myself this morning, I was that happy-go-lucky guy. That helped me throughout the day and that swim tonight."