Kuzul

The San Francisco Giants‘ starting rotation—which has been the foundation of the team’s run toward two World Series titles in the last three years—is struggling to open 2013.

The Giants’ 4.95 rotation ERA is the fifth worst in baseball entering play on Saturday. Giants starters have combined to allow a home run rate of 1.35 per nine innings pitched (HR/9), which is also fifth worst in baseball.

On the bright side, the season is only 17 games old. Thus, it’s way too early to get worked up over the rotation’s struggles.

It’s also too early to get overly excited about Madison Bumgarner’s tremendous start to the season. However, he sure does look like a Cy Young candidate through his first four starts. He’s 3-0 with a 2.05 ERA. He’s struck out 27 percent of the hitters he’s faced while walking only seven percent in 26.1 innings of work.

The other four starters have had their struggles though.

Opening Day starter Matt Cain has thrown well in two of his starts but been pounded in the other two. Barry Zito opened the year with 14 straight shutout innings before getting lit up for nine runs in 2.2 innings in his third start. Ryan Vogelsong has had just one quality start in three tries. The Giants are 3-0 when Tim Lincecum takes the ball, but he leads the National League in walk rate.

Let’s take a more in depth look at what’s going on with Cain, Zito, Vogelsong and Lincecum to open the year.

Matt Cain

Cain threw six shutout innings on Opening Day and was cruising through three scoreless innings in his second start. Then, things suddenly fell apart on him.

After retiring the first nine Cardinals hitters, Cain allowed seven hits, two walks and nine runs in the fourth inning. That was by far the worst inning of his illustrious career.

Cain bounced back with seven strong innings in his next start. However, the Brewers tagged him for seven hits, seven runs and three homers in his latest outing.

Looking at Cain’s overall stat line, his walk and strikeout rates are right in line with where they were last year. The biggest reason for his 7.15 ERA through four starts is the long ball. After allowing only 21 home runs in 219.1 innings last year, Cain has already allowed five in 22.2 innings this season.

Cain has allowed an astounding 15.6 percent of the fly balls hit off him to leave the yard this season. For his career, he’s allowed only 6.9 percent of the fly balls hit off him to go for home runs.

Thus, regression to the mean is almost assuredly coming. For that to happen, Cain is going to have to stop making so many location mistakes within the strike zone.

Once Cain gets his home run rate under control, his ERA should get back around the 3.00 level it’s been at for the last four years.

Barry Zito

Zito has had two great starts and one bad one. Last postseason, Zito was knocked out early in his first start before putting together two terrific performances in the NLCS and World Series. Two great starts, one bad start—that seems to be the trend with Zito.

With a fastball that sits between 82-85 mph, Zito has no margin for error. When he has command of his arsenal, he can rattle off seven shutout innings. When his command is a little bit off, he’s in trouble because he doesn’t have the velocity to get away with many mistakes.

After struggling through an injury-plagued season in 2011, Zito made 17 quality starts last year and finished with a 4.15 ERA. He made 19 quality starts and finished with a 4.15 ERA in 2010.

Expect him to finish with a 4.15 ERA and plenty of quality starts again in 2013. That’s perfectly adequate for a fourth starter, even if Giants fans were expecting more after his tremendous postseason and beginning to 2013. 

Ryan Vogelsong

Vogelsong’s issues appeared to be tied to a lack of fastball velocity in his first two starts of the season. He had to ramp it up earlier this year because of his participation in the World Baseball Classic, and that may have set him back.

After averaging around 91 mph with his fastball the last two years, Vogelsong averaged 88 in his first start and 89 in his second start, according to data from Brooks Baseball.

His velocity was back up to averaging 91 in his third start. Predictably, the results were back to being very good for Vogelsong. He had his first quality start of the year—going seven innings and allowing only five hits and three runs.

As long as Vogey stays in the low 90s with his fastball, he’ll have another excellent year for San Francisco.

Tim Lincecum

The Giants are 3-0 when Lincecum takes the hill this year. He beat the Dodgers in his first start of the season. He’s struck out 15 hitters in 16 innings, and opponents are only hitting .217 against him thus far.

So, all is well with The Freak, right?

Well, he’s also walked 12, allowed 12 runs and put up a 5.63 ERA in 16 innings of work. To be fair, nine of those runs came over two bad innings. On the other hand, those bad innings still count.

Taking the longer view, here are Lincecum’s numbers since the beginning of last season:

Can Lincecum turn it around? The Giants obviously believe that he can; otherwise, they probably would have traded him this winter or moved him permanently to the bullpen. Instead, they keep running him out there every fifth day in the hope that he’ll rediscover his former dominant self.

Lincecum was arguably the best pitcher in the game from 2008 through 2011. He won two Cy Young awards and was dominant as the ace of the staff during the Giants’ 2010 run to the World Series title.

His velocity is down a few ticks since then, but the stuff is still good enough dominate. The issue for Lincecum is pitch-to-pitch consistency. If he can start putting the ball where he wants to when he wants to, he can avoid the walks and the big innings that have plagued him for a year-plus now.

The Giants brass know pitching. The organization’s combined 3.45 ERA over the last four years is the best in baseball. Cain, Zito, Vogelsong and Lincecum are big reasons why the Giants have won two championships and had four straight winning seasons.

Their early season struggles are notable only because of their prior achievements. Cain will be fine once he gets his home run problem under control. The Giants know what they are going to get from Zito. It appears that Vogelsong has already turned the corner. Lincecum was once the best pitcher on the planet.

There’s 145 games left in the season. If the Giants rotation is still struggling around the trade deadline and it’s affecting their place in the standings, general manager Brian Sabean can address the problem then.

In the meantime, expect the game’s best pitching staff over the last four years to start to figure it out.

All statistics in this article are courtesy of FanGraphs and ESPN.

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