SAN DIEGO -- Obscured somewhat by the Mets' deflating ninth-inning collapse Friday night were two developments, one that delighted them, and one that should concern them. Oliver Perez pitched brilliantly for six innings and Frankie Rodriguez, even before he surrendered the game-ending grand slam to rookie Everth Cabrera, threw a number of fastballs that appeared to lack characteristic velocity.

The Mets embraced what clearly was Perez's best performance of the season and either ignored or denied what seemed evident to others, that Rodriguez's fastball was something of a misnomer. Pitching coach Dan Warthen, fully aware of Perez's maddening inconsistency, isn't convinced Perez is likely to give an encore performance. And manager Jerry Manuel said he isn't concerned about Rodriguez's velocity, but that the lack of command demonstrated in the 6-2 loss to the Padres did trouble him.

Both performances came in a game that was quite unsettling. After Perez had shut down offensively challenged Padres on a hit and a hit batsman for six innings, he allowed a run in a four-batter sequence in the seventh. But the Mets still led, 2-1, when K-Rod was summoned. Then, for the second time in four games, the Mets bullpen allowed five runs in the opponent's final turn at bat. Rodriguez retired none of the five batters, could not convert a save opportunity for the fifth time this season -- he has 24 saves -- and squandered successive save opportunities for the first time since 2004.

Three calls by plate umpire Marvin Hudson in the ninth inning upset the Mets and contributed to their seventh straight loss at PETCO Park. But none of what happened was as potentially damaging as the apparent lack of velocity by the closer.

A few teammates acknowledged the diminished speed, but neither Rodriguez nor Manuel did. The manager repeated his denials, identifying K-Rod's recent travails as "a bump in the road" and saying: "Health is not an issue. I've asked our medical people. They assured me there are no problems."

At the same time, the Mets could have been encouraged by Perez' work, had it lasted longer -- he threw 93 pitches in 6 1/3 innings -- or if they thought Perez had discovered a secret that would allow him to pitch consistently. One teammate suggested the unexpectedly good performance was the result of Perez returning to San Diego, where he began his big league career, and close to his native Mexico.

Another noted that Perez was due to pitch well, because he hadn't pitched all that well between his second start of the season -- against the Padres in April -- and his 11th start Friday night.

Warthen's take was this: "Ollie kept himself in the same place on the rubber, so his landing foot was in the same place. He was able to be more consistent with his pitches that way."

The pitching coach noted that Perez had paused in his windup as a means of "loading." And that helped too. Warthen said he repeatedly had urged Perez to make the pause. "But no more that two or three hundred times," he said, smiling.

And catcher Brian Schneider also noted that Perez had kept his arm angle consistent and hadn't dabbled in alternate pitches as he is wont to do.

"He was a little different [Friday] night," Warthen said. "We can't always get him there. Now the idea is to keep him there."