This might surprise some, but Luis Castillo was back in the lineup, hitting leadoff, the day after his dropped ninth-inning popup cost the Mets a 9-8 loss against the Yanks.

Castillo said he couldn’t sleep last night and was eager to get to the park today.

“I couldn’t wait to get to the game,” Castillo said. “It’s a new start today.”

The second baseman said he received several calls of support from friends last night, and now he’s set his mind on forgetting what, for now, goes as his most embarrassing moment on the field.

“I want to forget about everything from last night,” he said. “Everything about that game. I want to play and play hard.”

Manager Jerry Manuel didn’t have a second thought about putting Castillo back in the lineup. In his usual fashion—he has often shrugged off the gaffes that has cost his team games—he chalked this one up to the nature of the game. In other words, there’s no signs whatsoever that Manuel will remind his players that fundamentals—hustle, two-handed fielding, knowing the game situation—will become an overriding theme the rest of the season.

“It’s baseball,” Manuel said. “It’s part of the game. Obviously, you don’t like to go through this. But there’s 100 games left. The only thing that heals thing like this is time.”

Manuel said he gave Castillo a warm greeting upon arrival at Yankee Stadium, telling him “I couldn’t wait to see him.”

Very cuddly.

And he said he’s not worried about Castillo rounding back into the improved form he’s shown after a disastrous 2008 season.

“By the time we get back to Citi Field, he’ll be like 10-of-15 with five stolen bases,” Manuel said. “I’m not worried about that.”