Did the SF Giants make the right move in signing Sean Manaea?

Championship Series - San Diego Padres v Philadelphia Phillies - Game Four
Championship Series - San Diego Padres v Philadelphia Phillies - Game Four / Matt Thomas/San Diego Padres/GettyImages

While many of us were asleep, the SF Giants bolstered the starting rotation by signing left-handed hurler Sean Manaea. According to Jon Heyman of the New York Post, the deal is a two-year, $25 million pact with an opt-out after the first year. The Giants add a quality arm in Manaea, but was it the right move?

Did the SF Giants make the right move in signing Sean Manaea?

With the addition of the veteran starter, the Giants have seemingly rounded out the rotation. Manaea will be joining Alex Wood, Alex Cobb, Logan Webb, and Anthony DeSclafani as the five primary rotation arms as currently constructed. Jakob Junis will likely serve as a bulk innings arm, but I would expect another arm or two to join the competition.

The Giants' rotation was a strength in 2022 as it posted a 3.68 ERA, which ranked as the seventh-best mark in baseball. Of course, they had two of the best pitchers in baseball in Webb and Carlos Rodón. However, the latter is unlikely to return at this point.

The Manaea move potentially precludes the Giants from making another notable addition to the rotation. Things could change if they decide to move Wood to the bullpen.

Manaea has proven to be a reliable arm throughout his career. In seven seasons, the southpaw has registered a 4.06 ERA, 4.07 FIP, 1.22 WHIP, 8.1 K/9, and a 3.47 SO/W ratio. He has made over 25 starts in four of the last five full seasons.

The seven-year veteran was shipped to the San Diego Padres just before the start of the 2022 season. The Padres thought they were getting a mid-rotation arm, but Manaea struggled to the tune of a 4.96 ERA, 4.53 FIP, 1.29 WHIP, 8.9 K/9, and a 3.12 SO/W ratio in 30 appearances including 28 starts.

The good news was that Manaea handled nearly a full workload. The bad news was that he put together a subpar performance. Perhaps, an even more concerning number was a 1.71 HR/9 rate, which was the highest in baseball among pitchers with at least 150 innings pitched last year. That is a trend that has quietly increased in recent seasons.

On the one hand, the Manaea addition has the potential to be a nice value signing. In six seasons with the Oakland A's, he tallied an ERA below four in three of six seasons. There is a possibility that his rough 2022 campaign was an outliet.

On the other hand, Manaea does not meaningfully improve the rotation. At his best, he is a mid-rotation arm who fills up the strikezone and works quickly. The Giants like these traits in a pitcher, but his signing is yet another low-risk move that does not have the high upside of a Carlos Rodón.

The Giants are seemingly accepting that the rotation will be worse next year. It still has the potential to be a quality unit. And, if every starter has a career year, they may even be able to squeak into the playoffs, but this rotation is not strong enough to carry them further.

Good teams have multiple top options, whereas the Giants have an ace in Logan Webb to go along with a handful of quality arms. That is good, but it is not enough. Unfortunately, that seems to be just fine by the Giants.