How Jeff Samardzija’s shoulder injury affects his future with Giants and the team’s rotation

After allowing six home runs while striking out just five hitters in his three starts this season, Giants pitcher Jeff Samardzija is headed to injured list and could potentially stay there much longer than the minimum 10-day requirement.

Manager Gabe Kapler revealed Saturday that Samardzija has a right shoulder impingement and is set to undergo a MRI in Los Angeles. If the diagnosis reveals a significant issue, it’s possible Samardzija’s career with the Giants is over.

Following an outing in which he gave up homers to three different Dodgers sluggers, Samardzija told the Giants medical staff he struggled to get his right shoulder loose while warming up.

“Shark shared that he just had trouble getting loose and he wasn’t able to rip his pitches the way he wanted to,” Kapler said. “That certainly makes an impact on a pitcher’s ability to perform.”

A blister on Samardzija’s right hand has prevented him from throwing his splitter this year and limited his effectiveness against the Padres, Rangers and Dodgers, but the 12th-year veteran’s shoulder ailment is clearly a more concerning injury.

Given his previous history of shoulder trouble, the injury is frustrating news for a starter in the final weeks of a five-year, $90 million contract he signed with the Giants in December, 2015.

Samardzija was limited to 10 outings during a rough 2018 season due to a shoulder injury that proved difficult for the right-hander to overcome. Samardzija didn’t need surgery and only complained of inflammation at the time, but he repeatedly said he struggled to “get loose” in the bullpen and wasn’t able to generate the necessary arm speed to maintain his effectiveness.

Kapler said it was too soon to connect the shoulder issues Samardzija is dealing with right now with what he faced in 2018, but the similarities are obvious.

Much like in 2018, Samardzija isn’t generating swings and misses, his command with several different pitches is off and his fastball isn’t missing bats. When he returned to the mound in 2019, Samardzija emerged as the Giants’ most reliable starter and posted a 3.52 ERA over 181 1/3 innings, but he also admitted his preparation process –particularly during the offseason– would need to change for the remainder of his career if he hoped to avoid more shoulder issues.

With Samardzija and left-hander Drew Smyly (left index finger strain) on the 10-day injured list, the Giants are now without two of their projected starters and unsure of how they’ll fill the void in their starting rotation.

Left-hander Tyler Anderson took Smyly’s turn in the rotation Thursday in Colorado and threw five scoreless innings against his former club. But Anderson was limited to 66 pitches and it’s unclear if the Giants would feel comfortable pushing him past 80 in his next outing.

Another left-hander, Andrew Suárez, was called up from the Giants’ taxi squad to take Samardzija’s roster spot Saturday, but Kapler indicated he wanted to have Suárez as an option in the bullpen immediately, particularly if the club needs a pitcher to work multiple innings at a time in relief.

Suárez has starting experience in the past, but given the state of an overworked bullpen, it’s likely he’ll be used within the next few days.

The most likely candidate to replace Samardzija in the rotation on Wednesday in Houston might be minor league free agent Trevor Cahill, who has spent the last two weeks working out at the Giants’ alternate site in Sacramento after a fingernail injury prevented him from making the Opening Day roster.

Cahill was initially viewed as a “bulk innings” pitcher who could swing back and forth from the rotation to the bullpen as needed, so the Giants could add him to the roster in the coming days.

Kapler mentioned that Cahill pitched well in an intrasquad outing on Friday in Sacramento and also noted he had been built up beyond three innings earlier in the week.

Through 15 games, the Giants haven’t received a quality start — 6 innings, fewer than four earned runs — from any of its pitchers. They would love to have Cahill in a position to work deep into a game and save the bullpen if he does make his first appearance next week.

With two starters sidelined and two others –Johnny Cueto and Kevin Gausman– sporting earned run averages hovering around 5.00, the Giants will have to take what they can get from their remaining healthy options.

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