Activated from the 15-day disabled list and playing right field for the opener of a four-game set against the Houston Astros on Friday night, Church was bouncing around a clubhouse he mostly avoided for the past couple of months while going through a frustrating recovery from post-concussion syndrome.
"I'm really excited to get back in here. We're in a playoff race," Church said. "Hopefully I can contribute, help out, do whatever it takes. I feel great."
Church, batting seventh Friday night, last played on July 5 -- six days after he came off the DL for the first time because of a concussion. The Mets were in third place in the NL East, 3½ games back.
Church batted .105 (2-for-19) in six rehab games, but isn't worried that he might not be ready to take over his spot in the outfield and disrupt a lineup that has won nine of 10 with help from Fernando Tatis in right field.
"There are no feelings of dizziness or loopiness, anything like that," Church said. "Hopefully I'll fall right into it, right into the flow of things and just help out, be a piece, be a piece of the puzzle.
"I know that [manager] Jerry's [Manuel] going to look after me, give me some days off, just to get my legs, settle in," he added.
Manuel said Church, who sustained a concussion on March 1 in a collision with teammate Marlon Anderson and a second one on May 20 trying to break up a double play, will play Friday and Saturday, then sit against a lefty starter on Sunday, which happens to be a day game following a night game.
Tatis who hadn't played in a big league game since 2006 before being called up May 13, has filled in admirably for Church and Alou, hitting .297 with 10 homers and 38 RBIs. Manuel said Church will be the starter because of the "type of season he was having" before his injury.
"If we get what we had with him in the first part of the year it will be a great addition to our lineup, a tremendous addition to our lineup," Manuel said of Church, who was hitting .307 with 10 homers and 36 RBIs in 57 games.
Manuel didn't quite give Castillo the same endorsement when he announced the second baseman would be activated on Saturday after there were discussions that he might need further rehab before rejoining the team.
Out with a strained left hip flexor, Castillo used up his allotment of minor league rehab games, and was in New York to work out for the Mets' coaches and formulate a plan for his return. But Manuel said he "looks good, looks real good," and he would start Saturday.
Castillo, who said he lost "a couple" of pounds during rehab to take the stress of his legs -- his quadriceps have also bothered him -- is ready to fill any role he is asked to play.
Castillo was batting .261 with 42 runs scored and 26 RBIs in 245 at-bats when he went on the DL on July 3.
"I'm ready to go," Castillo said. "Whatever Jerry wants. ... I don't know what's in Jerry's mind."
Manuel said there was no consensus on who will be sent down. Third-string catcher Robinson Cancel was optioned to Triple-A New Orleans to make room for Church, but Manuel is happy with the play of rookies Argenis Reyes at second, and Nick Evans and Daniel Murphy in left field.
"It's a tough decision, very tough decision; been wrestling with this," Manuel said. "We will consider everything."