Mamiit ran into a stonewall in classy Denis Istomin on Sunday and the Uzbekistan No. 1 clinched the Davis Cup Asia-Oceania Group 1 relegation tie with a surprisingly easy 6-3, 6-0, 6-4 victory over the flamboyant Filipino-American.

Istomin punished Mamiit right from the start with a splendid all-around performance, winning in just one-hour and 55 minutes at the Philippine Columbian Association courts to deal the Filipino star his worst Davis Cup defeat.

Eric Taino earned some consolation of sorts by besting Vaja Uzakov, 6-4, 6-4, in the meaningless second reverse singles that pegged the final score at 3-2.

“He (Istomin) had answers to everything,” said Mamiit, who lost for just the second time in 12 Davis Cup matches. “I tried everything I got, did whatever I could. But I guess that’s the way it goes.”

Istomin, the world No. 156 who opened things up for Uzbekistan with a straight-sets win over young Patrick John Tierro on Friday, broke Mamiit in the fifth game of the third set to secure the match.

The Uzbek served out the encounter at love.

Mamiit immediately went to the Uzbekistan bench and congratulated each member of the team before returning to the court to address the crowd. He tapped his chest lightly as if to tell them that even his big heart couldn’t get him past the big Uzbek.

“I felt like I fought really hard for my country,” said the 31-year-old Mamiit, who will head back to the United States to play a full schedule in the pro tour and try to get back into the world’s Top 100.

“We just have to keep on building, there’s a lot of potential for Philippine tennis,” added Mamiit, who kept on egging himself up between points during the match. “I think the key here is that we all have to believe that our country belongs to this group.”

The loss dropped the Philippines back to Group 2 where it will play against Kazakhstan in September, which lost to Taiwan 3-2.

The Philippines fell on the brink on Saturday when Mamiit and Taino, the two figures chiefly responsible for resurrecting tennis in the country with several Southeast Asian Games gold medals and an Asian Games bronze, lost the doubles to Istomin and Farrukh Dustov in four sets.

“It was a match that could have gone either way,” Mamiit said of the 6-7 (10-12), 7-5, 1-6, 5-7 loss. “Had we won that match, the pressure would have been on him (Istomin) today.”

The first Philippine victory belonged to Mamiit on Friday when Dustov surrendered in the third set as the Uzbek cramped up on both thighs.