SAN FRANCISCO -- Seattle Mariners outfielder Victor Robles injured his left shoulder and was carted off the field after making a dazzling catch in the ninth inning of a 5-4 loss to the San Francisco Giants on Sunday.

Robles was playing right field when he made a long dash to chase down a fly ball hit by Patrick Bailey. He went over the low railing in foul territory to make the catch, fell over the wall and crashed into the netting in the process. Robles appeared to be in immediate pain, flipping the ball away with his right hand and grabbing at his left arm.

Mariners manager Dan Wilson said Robles has a shoulder-related injury and was having tests done at Oracle Park.

"He's such a force," Wilson said. "Big hits, the great defense that he plays. He causes a lot of havoc on the bases, doing what he does out there. He's a great guy to have at the top of your lineup. That's why we're hoping for the best."

The 31-year-old Robles is hitting .273 with 3 RBIs and 3 stolen bases through 10 games this season after hitting .328 for the Mariners last season and going 30-for-31 in stolen-base attempts. He was the first Seattle player with a batting average of over .320 since Ichiro Suzuki hit .352 in 2009.

The Giants, who won the game on the next pitch on a single by Wilmer Flores, challenged the call that it was a catch, but it was upheld.

Center fielder Julio Rodriguez was the first to wave over athletic trainers after seeing Robles go down, and he called Robles a "very impactful player for our team, defensively and offensively."

"I just noticed that he was in pain and called the trainers immediately," Rodriguez said. "He made all that effort, but it was at a high cost."

Giants right fielder Mike Yastrzemski, who knows the dimensions of the ballpark well, said he was glad that netting was there as opposed to the concrete bricks that align the right-field wall.

"Who knows what could have happened?" Yastrzemski said. "It's one of those things where you hope he's OK. I've never seen anything like that."

Robles could have probably let the ball go foul, but "that's not who he is," said Bryan Woo, who started for the Mariners.

"He's got the respect of everybody in the clubhouse," Woo said.