After a recent slew of injuries, the San Francisco Giants’ biggest overall weakness has quickly been exposed.

The team lacks depth, a fact that could go on to plague them as the season continues.

Ryan Vogelsong and Santiago Casilla are on the disabled list. Angel Pagan is nursing an injured hamstring that has kept him out of the lineup since May 25. Jovial third baseman Pablo Sandoval will at the very least miss the weekend series against the St. Louis Cardinals due to an injured foot.

When Vogelsong first went down nobody was particularly rattled. Considering how poorly he had been pitching, some fans may even have thought that the Giants would be a better team without the well-traveled right-hander.  

But after an uninspiring list of possible replacements eventually yielded Mike Kickham, a rookie who lasted only 2.1 innings in his major league debut against the Oakland Athletics, Vogelsong’s absence suddenly looms quite large.

The Giants’ starting rotation has been horrible so far this season (17-18, 4.77 ERA), and Vogelsong has certainly been a big part of that. But he looked to have finally put things together on the night he fractured his hand, throwing five shutout innings against the Washington Nationals before incurring the unfortunate injury.

Now that Kickham’s trial run has failed, the Giants—due to lack of a better option—are turning to long reliever Chad Gaudin, who will take the ball Sunday against the Cardinals.

But that creates another problem.

With Santiago Casilla on the disabled list, the Giants’ bullpen is already weakened significantly. Take Gaudin—who has posted a 2.05 ERA on the season—out of the equation, and the group as a whole could suddenly be very vulnerable.

George Kontos, who has been filling Casilla’s normal seventh-inning role, has not been effective. In 26.1 innings, the right-hander has a lofty 5.13 ERA. He allowed two run-scoring hits to Yoenis Cespedes in the recent series against the Athletics.

Jean Machi has been good, but he’s still an unproven commodity at this point. Ramon Ramirez’s promotion from Triple-A could last only until the Giants feel Heath Hembree is ready to contribute at the big league level. 

According to Andrew Baggarly of CSN Bay Area, that moment could be soon:

I asked Bochy and he said Hembree is close to being deemed ready to face major league hitters. I do think we’ll see him at some point this season. But as it was explained to me, the Giants don’t want to bring him up as an extra arm. They are grooming him for a late, leveraged relief role and don’t want to throw him in there until they absolutely feel the time is right. That could be a week or two from now. It just depends on how the bullpen comes together now that roles are being shifted around a bit. 

Outside of Sergio Romo, Jeremy Affeldt and Javier Lopez, the Giants’ bullpen is a major question mark. If the starting pitchers continue to show an inability to pitch deep into games, the Giants could be in trouble.

But, unfortunately for the Giants, their pitching isn’t the only problem.

Up to this point of the season, the Giants’ offense has been able to pick up the slack. The team has managed to post 16 come-from-behind victories, allowing them to stay afloat in a surprisingly competitive division.

But with Pagan out of the lineup and Sandoval battling the flu before sustaining the foot injury, the top of the order has been relatively punchless.

Since Pagan last played on May 25, Giants’ leadoff hitters have gone a combined 3-19. The center fielder is likely slated to return to action on Sunday, according to Alex Pavlovic of the San Jose Mercury News.

Having the usual leadoff hitter back in the lineup will be a relief for the Giants, even though Pagan’s numbers have been subpar so far this season (.262 batting average, .314 on-base percentage).

With a very difficult June schedule looming, the Giants have picked a bad time to catch the injury bug. After they finish in St. Louis, the Giants travel home for a quick two-game series against the Toronto Blue Jays before hopping right back on the road for nine games against the Arizona Diamondbacks, Pittsburgh Pirates and Atlanta Braves.  

Now is when a deep bench and major league ready talent waiting in the wings would be a welcome sight.

But the Giants have neither.

With Sandoval ailing, Joaquin Arias and Nick Noonan will replace him at third base.

On the season, Arias is hitting .220 with a .267 OBP. His action has been limited, only garnering 41 at-bats in 37 games. Noonan, after a hot start, has been even worse. Through 32 games, the rookie infielder is hitting just .216 with a weak .508 on-base plus slugging percentage (OPS).

As poor as Noonan and Arias have been thus far, the Giants clearly don’t have confidence in their minor league replacements, or else they would be up with the big club right now.

Kensuke Tanaka, the Japanese import, is playing well in Fresno. In 171 at-bats, the infielder is hitting .310 with a .374 OBP. But he had some severe defensive issues in spring training, forcing the Giants to choose Noonan to be their utility infielder.

Other than Tanaka, who is still struggling with his defense (.938 fielding percentage), there are no inspiring options to replace Noonan on the roster.

If Pagan is unable to fend off his hamstring injury, the Giants would be looking at a potential starting outfield of Andres Torres, Gregor Blanco and Hunter Pence.

While Torres has been decent at the plate so far (.276 AVG, .321 OBP), his defense in left field has been suspect, to say the least. Blanco has struggled lately at the plate, dropping his batting average to a weak .268. Hank Schulman of the San Francisco Chronicle recently said:

For all the bellyaching I’ve seen on Twitter about Andres Torres lately, he was hitting .287/.333/.416 before his 0-for today. In his past eight games he was 12-for-25 with six doubles. That’s not bad for a guy who was signed to be a platoon No. 7 hitter. I’d be more concerned with the defensive lapses the past couple of days, but he’s been pretty good in left field overall. Blanco’s been the one struggling. He’d benefit from a return to the seventh spot when Pagan returns.

Pence has been his usual productive self, but the Giants simply won’t be able to score many runs as long as Torres and Blanco are starting on a daily basis.

In the minor leagues, only a few outfielders have shown that they may be ready to contribute at the big league level. Roger Kieschnick, the Giants’ third round pick in the 2008 draft, has been especially impressive. Through 49 games in Triple-A Fresno, the right fielder is batting .313 with seven home runs and a .974 OPS.  

Besides Kieshnick, the Giants’ only other minor league option is Francisco Peguero, although he’s been unimpressive in his two major league cameos.

The reality is that the Giants simply aren’t a club built to sustain any prolonged absences of their key players, a fact that was made painfully obvious in 2011 when Buster Posey suffered his traumatic injury.

If the Giants are going to defend their World Series title, they will have to get healthy—and fast.

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