SAN FRANCISCO -- The Giants¡¯ catching situation became even more precarious on Friday afternoon, when veteran Roberto Pérez was forced to exit the club¡¯s 3-1 loss against the Royals at Oracle Park with a right shoulder strain.

P¨¦rez got the starting nod behind the plate for the fifth time in the Giants¡¯ first seven games, but he hurt his throwing arm while attempting to throw out Kyle Isbel at second base in the sixth inning. P¨¦rez immediately grimaced in pain and promptly exited the game accompanied by Giants athletic trainer Anthony Reyes, a sobering scene that dampened the festive vibes of the club¡¯s home opener.

Manager Gabe Kapler said P¨¦rez felt a ¡°zing¡± in his shoulder, but the Giants have yet to determine the severity of the injury. The 34-year-old veteran landed on the injured list with right shoulder trouble twice in the past, missing 18 games in 2020 and 38 games in ¡®21.?

¡°Pretty tough,¡± said right-hander Alex Cobb, who was charged with the loss despite holding the Royals to two runs on seven hits over seven innings. ¡°I know he battled last year with some injuries and he¡¯s such a quality player when he¡¯s healthy. I know he¡¯s looking for a bounceback year and showing everybody he's healthy. I¡¯m not going to be too doom and gloom about it. Hopefully he gets it checked out, and it¡¯s something minor. But it¡¯s never a good sign when you¡¯re getting helped off that way.¡±

Rule 5 Draft pick Blake Sabol jogged in from left field to replace P¨¦rez behind the plate, with LaMonte Wade Jr. shifting to the outfield and Wilmer Flores entering the game at first base.

The mid-inning position switch capped an eventful day for Sabol, who also made a juggling catch in left and delivered a RBI single to drive in the lone run of the afternoon for the Giants, who continued their boom-or-bust ways by collecting only five hits against Brad Keller and three Kansas City relievers. ??

¡°I¡¯m hoping Roberto is OK,¡± Sabol said. ¡°I haven¡¯t heard anything about it yet. For me, I¡¯m just going to control what I can control and give my team my best. I¡¯ll be ready to go wherever the team needs, whether that¡¯s back in the outfield or back behind the plate for the next couple of weeks.¡±

The Giants were already down one catcher, as Joey Bart landed on the 10-day injured list with a mid-back strain last week. Bart is progressing well and could begin a rehab assignment in the next couple of days, but he won¡¯t be eligible to return until Monday at the earliest.?

P¨¦rez¡¯s injury leaves Sabol as the only healthy catcher on the 26-man roster, which could force the Giants to add Austin Wynns, the odd man out of the four-man catching competition this spring, or two-time All-Star Gary Sanchez, who joined the club on a Minor League deal last week.?

Wynns entered Friday 2-for-13 (.154) with one home run through his first four games at Triple-A Sacramento, while Sanchez has yet to report to a Minor League affiliate as he continues to build up in extended spring camp in Arizona. Neither is on the 40-man roster, so the Giants would have to clear a spot for both of them.

¡°You break camp, and you feel pretty thick at that position,¡± Cobb said. ¡°A week in, blink of an eye, and you¡¯re looking around [wondering] how we¡¯re going to piece it together. Not an ideal start. Hopefully Joey is on the back end of what he has going on, and hopefully Roberto has a bounce back as well to whatever he had going on today.¡±

P¨¦rez, a two-time Gold Glove Award winner, served as the Giants¡¯ Opening Day catcher after making the team as a non-roster invitee, but there were questions about how much of the catching workload he¡¯d be able to handle after appearing in only 65 games over the past two seasons due to injuries. Still, the Giants will be hard-pressed to replace the defensive prowess and calming presence he brings behind the plate.?

¡°The game is slow to him,¡± Cobb said. ¡°He sees things. He¡¯s seen it all. He¡¯s been out there. You can¡¯t replace reps. We¡¯re going to try to get Sabol up to speed in the big leagues, but he hasn¡¯t seen what Bebo¡¯s seen back there. There¡¯s just instincts to the game that you can¡¯t really teach. It¡¯s only on-the-job training. That¡¯s pretty invaluable.¡±