Mets' Francisco Lindor takes some rusty swings against Noah Syndergaard

SAN FRANCISCO — More than four hours before first pitch, the typically mundane pregame activity came with a main event Tuesday: Noah Syndergaard against Francisco Lindor and Luis Guillorme in live batting practice.

For Syndergaard, it was his first time facing hitters since May, when right elbow inflammation set him back in his return from Tommy John surgery. He threw one simulated inning — 15 to 20 pitches, all fastballs and changeups.

For Lindor and Guillorme, it was their first time facing full-speed pitching since suffering their injuries — Lindor’s strained right oblique on July 16 and Guillorme’s strained left hamstring on July 31.

"Productive for both guys," manager Luis Rojas said of Syndergaard and Lindor.

The switch-hitting Lindor took all of his at-bats as a righthanded hitter. He did stand in the lefthanded hitter’s box but was limited to tracking pitches — i.e., watching them go by — because his progression from that side is delayed by the oblique issue.

"It was a good start," said Lindor, who also fielded ground balls, ran the bases and thanked the Giants’ grounds crew at the end of his workout.

Lindor and Guillorme also faced Andrew Mitchell, a lefthander who is with the Mets as part of the taxi squad. It was against Mitchell that Lindor hit his lone ball in play, a drive off the wall in centerfield.

"Everything else was foul, foul, foul," Lindor said. "I was trying to stay up the middle and I actually got one up the middle, which is good. Swung and missed twice and a bunch of foul balls and I put one in play."

Lindor is hoping to return to the Mets without going on a minor-league rehabilitation assignment. But it is not clear if he will avoid that fate. Rojas said, "It could happen."

"Nobody wants to go to the minor leagues, but if I end up going, [it’s fine]," Lindor said. "I can’t say no, I’m not going, I’m going to stay up here. I would love to say that, but at the end of the day, they know more than me when it comes to those things."

Rojas added, of Lindor’s activities: "It’s even more than going on a rehab assignment."

Guillorme also ran at close to 100%, according to Rojas, and participated in defensive drills. He is likely to go on a rehab assignment because "testing and running in an actual game is different" with a hamstring injury, whereas Lindor hurt his oblique.

Daily Baez

An increasingly spry Javier Baez (back spasms) fielded ground balls at shortstop and second base, plus hit in the indoor batting cage.

"He feels good — or better, I should say," Rojas said.

The Mets are strongly considering sending Baez on a rehab assignment before activating him from the injured list.

Sending him across the country to a minor-league affiliate during the Mets’ West Coast trip would suggest he won’t return until the start of the next homestand (Tuesday) at the earliest, as opposed to the first day he is eligible (Sunday).

"We don’t know. Let’s stick to today being a good day," Rojas said. "I didn’t expect him to be moving like he did today. He actually looked really good."

McCann out

Catcher James McCann, dealing with back spasms, was scratched from the Mets’ lineup minutes before first pitch. Patrick Mazeika replaced him.

Extra bases

Dominic Smith was out of the lineup so Kevin Pillar could play, Rojas said. The Mets liked the matchup of Pillar against righthanded starter Logan Webb. Pillar entered with a .167/.186/.238 slash line in the second half. "We know [Smith] hasn’t been swinging really good in the last couple days," Rojas said. "Get Kevin in there, get him involved and see if we can get him going, too. Why not?" . . . The Giants scratched Kris Bryant from the lineup with a tight left hamstring.