HOUSTON -- As Astros pitchers and catchers hit the field at the club’s Spring Training facility in West Palm Beach, Fla., on Thursday for the start of camp, several players were unable to attend the first official workout because of the intake procedures players and staff were required to go through. It wasn’t immediately made available which players weren’t at Thursday’s initial workout.

According to general manager James Click and manager Dusty Baker, the absences stemmed from a combination of inconclusive test results, as well as additional heart testing for those players who were found to have antibodies.

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“It’s not that we anticipate them being not here for a significant period of time, but if certain things show up in testing or physicals, we have to go through additional clearances, which should take a little bit of time,” Click said. “But we hope to have it resolved very soon.”

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Baker endorses COVID-19 vaccine

Baker, a 71-year-old cancer survivor, said Thursday that he received his second COVID-19 vaccination Feb. 4. Baker also said he received a flu shot in November for the first time in his life after team doctors warned him about possible complications from his previous conditions, including a heart condition.

Baker said he was hesitant about getting the COVID-19 vaccine until he was swayed by a doctor explaining the effectiveness of the vaccine on television. Baker said his 89-year-old mother, who resides in assisted living, has decided not to get the vaccine.

“I was a little leery about getting the vaccine until I saw the number of deaths and the number of people that got sick all over the world,” he said.

Now that he’s had the vaccine, Baker said he did some public-service announcements while at home in the Sacramento, Calif., area to push for others to get vaccinated. Major League Baseball isn’t requiring players to get a COVID-19 vaccine, though the MLB Players’ Association is strongly encouraging it.

“It’s up to the individual,” Baker said. “I’m not going to try to convince those who are staunchly against it, but those who are on the fence or on the bubble, maybe my words will sway them one way or the other.”

Baker ‘super thrilled’ for Brantley’s return after losing Springer

Baker only had a chance to manage All-Star center fielder George Springer for 60 games last year, saying Thursday he was just getting to know Springer before the season ended. Springer, of course, signed with the Blue Jays, and Baker said he reached out to Springer to tell him congratulations.

“It’s always tough to replace those guys,” he said. “You’re not going to replace him with one man. You’re going to have to replace him by other people stepping up and that try to replace George. It’s a situation where we’re looking for a surprise. I’ve always said that every spring we’re looking for a surprise player, looking for a surprise pitcher that you weren’t counting on over the winter that got stronger or just put everything together. We’ve got our eyes wide open. There are some spots and some jobs to be won. You’re not in the giveaway business; we’re in the earn-it business, and we’re going to give some guys a chance to earn their keep.”

After Springer signed with Toronto last month, reports surfaced that Michael Brantley was following him north of the border. Baker was just wrapping his mind around losing Brantley, too, when he got a phone call that Brantley was re-signed to a two-year deal to remain in Houston.

“I was super thrilled,” he said. “I was just making a call to Michael to tell him, you know, I’m going to miss him, just like George. … What a big change of emotions. I would have loved to have both of them back, but I’m glad we have one of them back. But Michael is a big part of this ballclub as a player and person and one of the real leaders on this team.”

Pettis out until regular season

Astros third-base coach Gary Pettis, who was diagnosed last year with multiple myeloma, will miss Spring Training while he undergoes treatment near his home in California. The team said Thursday that Pettis’ absence this spring isn’t related to the progress of his recovery.

“I’m doing very well, but my doctors felt that due to some potential logistical issues caused by the ongoing pandemic, it made sense for me to continue with my treatments here at home,” Pettis said in a statement. “They are being cautious with me, which I understand. I’m doing great and will be back with the ballclub, but it will be later than we had thought.”

Pettis left the Astros after their Sept. 15, 2020, game because of hip discomfort, which led to the diagnosis of multiple myeloma. The American Cancer Society defines multiple myeloma as a cancer of plasma cells. Baker said Pettis is very much still helping the club from afar.

“I’ve been in contact with Gary all winter,” he said. “I talked to him three or four times a week. … With the advent of Zoom, he’s still with us. We’re the Zoom-ingest people I’ve ever met in my life. Gary’s an expert now in Zoom, and he’s still here with us. We don’t know exactly when he’ll return, but it should be sometime next season and in the upcoming weeks.”

Pettis, 62, is in his seventh season as Houston’s third-base coach after spending eight years with the Rangers as their third-base coach (2013-14) and first-base coach (2007-12). He also served on the Major League staffs of the Mets (2003-04) and White Sox 1997-02) and had a handful of Minor League coaching stops. A five-time Gold Glove Award winner, Pettis played 11 years in the big leagues with the Angels (1982-87), Tigers (1988-89, '92), Rangers (1990-91) and Padres (’92).

Skeeters to open season April 8

The Sugar Land Skeeters, who will begin this season as the Astros’ Triple-A affiliate, will open their season April 8 on the road against Reno. The home opener at renovated Constellation Field, which is only 23 miles from Minute Maid Park, will be on April 22 against the Salt Lake Bees.

Major League Baseball announced the 2021 Minor League Baseball schedule on Friday. Triple-A teams will play 142 regular-season games, and Double-A and Class A teams will play 120 games, beginning their seasons on May 4. Double-A Corpus Christi will open its season May 4 against San Antonio.

The 2021 MiLB schedule will feature improved travel due to the better geographic alignment of teams. The Astros purchased an ownership stake in the Skeeters, who were previously an independent team, and own Corpus Christi, putting their top two affiliates in Texas. Both of Houston’s Class A affiliates are in North Carolina: Class A in Fayetteville and Class A Advanced in Asheville.

The Fayetteville Woodpeckers open the season May 4 on the road against Carolina, and the Asheville Tourists will begin May 4 at home against Brooklyn.