Willie Randolph made it clear that even when Anderson Hernandez comes off the disabled list, Kaz Matsui is the Mets’ starting second baseman.

Beleaguered Matsui is doing his best to repay that faith with solid defense and an occasional big hit, like the go-ahead, two-run double in yesterday’s 6-5 win over the Braves.

With the Mets trailing arch rival Atlanta 3-2 in the seventh inning, Jose Reyes tied the game with an RBI single, and Matsui worked a full count against Braves ace Tim Hudson. Matsui then laced an inside fastball to right field to plate Rayes and Jose Valentin with go-ahead runs the stretched-thin bullpen made stand up.

“Kaz is playing well for us right now. He’s playing good defensively, and getting his hits here and there,” Randolph said. “Anderson is going to be in rehab down there [in the minors], and we’ll monitor how he’s doing, but Kaz is playing pretty well and he’ll be here. [Hernandez] will go to Triple-A.

“Kaz is just getting better and better every day. I like his defense even more than his offense. He’s doing a great job for us; those are big hits for us, and he’s going to get stronger as he gets more comfortable in the field.”

After returning from the DL red-hot (.344 through his first eight games back), Matsui had been slumping. He was 3-for-26 until that huge double.

“I’m happy about it, especially given that situation and I was able to come through. I have confidence in myself, and I just want to do whatever I can, know my role and do what’s asked of me,” said Matsui, who got cheered by the 48,369 on hand at Shea, a fist-pound from Reyes coming off the field, and congratulations in the clubhouse from Ramon Castro – in Japanese.

“I appreciate it [the cheers]. I can accept it honestly, because they’ll applaud me if I do good, or they’ll boo if we don’t,” Matsui said of the fans. “It’s just the way it goes. Sometimes they boo out of expectations and you have to accept that as well.”