Jon Ackerman, NBC Olympics

LONDON — Despite an unbeaten all-time record at the Olympics, which has given Misty May-Treanor and Kerri Walsh Jennings two gold medals, they knew things would be tougher this time around. So far, they’ve been right.

The two-time reigning champions won their second match of the London Games on Monday night, bringing their all-time record in three Olympics together to 16-0. Further exhibiting their dominance is the fact that they are 32-0 in sets played. And only one of those sets has gone past 21 points.

But they’re not rolling through opponents in London. In their opening match Saturday against Australia’s Natalie Cook and Tamsin Hinchley, May-Treanor and Walsh Jennings didn’t pull away in the first set until 18-18. In the second game, they trailed 13-9 and 16-14 before pulling away from a 19-all tie.

On Monday against Kristyna Kolocova and Marketa Slukova of the Czech Republic, the Americans saw their first “easy” set, winning game one 21-14. But they trailed much of the second, calling a time out after falling behind 18-15. Three straight points out of that break tied the score, and forced the Czechs into a timeout.

Kolocova and Slukova grabbed the next point, but May-Treanor and Walsh Jennings closed things out with a 3-0 run to win 21-19. Perfect records intact.

The Americans’ coach, Marcio Sicoli, credits their physical and mental training.

“We have tried to incorporate a new thing in our training, that is all the matches are going to be (close),” he said. “Beach volleyball grew so much (since 2008), like every country has great teams right now, (from) first round all the way to the finals. And I think the difference will be the team that’s going to be able to be comfortable in those pressure situations, on 18-18, 19-19. And I felt that our training and our psychological training has been doing really good for us.”

Before this week they hadn’t really been pushed at the Olympics, but no one in the world knows how to deal with the pressure of the Olympic spectacle more than May-Treanor and Walsh Jennings. And outside of the Olympics, they’ve had more tight sets in their careers than some of their competitors do total matches.

May-Treanor turned 35 on Monday, and Walsh Jennings turns 34 in two weeks. The women they played from the Czech Republic were both 24.

It was clear who was comfortable in the pressure situations Monday night.

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