The signing: The San Francisco Giants sign Johnny Cueto for six years and $130 million, with Cueto having an opt-out clause after two years.

Johnny Cueto and Jeff Samardzija had a combined second-half ERA last year of 5.29

— Jeff Sullivan (@based_ball) December 14, 2015

Cueto entering his age 30 season. Greinke entering his age 32 season. I understand aging curves but 6 yrs for Cueto & not Greinke baffles me

— Wendy Thurm (@hangingsliders) December 14, 2015

Total money spent on starters this offseason: $943,300,000. Add in relievers, and teams have spend $1,120,950,000 -- $1.12B -- on pitching.

— Jeff Passan (@JeffPassan) December 14, 2015

Cueto turned down $120 million from the Diamondbacks and gets the bigger payday he anticipated, one of many such gigantic payouts this offseason for pitchers. It's certainly interesting that starting pitching has been the big priority, even though we're in the midst of one of the lowest-scoring eras in baseball history and pitchers carry more risk due to their potential to break down. It's also interesting to note that none of the recent World Series champs has had a particularly dominant starting rotations (via FanGraphs):

2015 Royals: 22nd in majors in rotation WAR

2014 Giants: 23rd

2013 Red Sox: 13th

2012 Giants: 16th

2011 Cardinals: 14th

2010 Giants: 14th

2009 Yankees: 8th

Maybe those numbers are misleading in some shape? The 2010 Giants, for example, did rank third in the majors in rotation ERA behind Tim Lincecum and Matt Cain. Why is their WAR ranking lower? Park effects. Giants pitchers benefit from their pitcher-friendly environment.

Of course, rotations become even less important in the postseason, when more off days mean you can use your best relievers more often, and you don't even need to use your No. 5 starter. The bet front offices are making is pitching depth is what gets you into the postseason, and that's all you can really ask for: Get into the tournament and get hot at the right time.

Anyway, with Lincecum and the retired Tim Hudson dropped from the payroll, the Giants had some money to spend. They got Jeff Samardzija and now they got Cueto.

The reason: The Giants had a bad rotation in 2015, ranking seventh in the NL in rotation ERA, 12th in road ERA, and 25th in the majors in FanGraphs WAR. Hudson retired, Lincecum and Ryan Vogelsong are free agents after ineffective seasons, Cain hasn't pitched well since 2012 and rookie Chris Heston had a terrible second half. After striking out on Jon Lester last offseason, and David Price and Zack Greinke so far this offseason, they're gambling that Cueto's inconsistent results with the Royals aren't related to the sore elbow he had earlier in the 2015 season.

It is interesting that the Giants went six years on Cueto after apparently not wanting to on Greinke. There has to be concerns about what happened in Kansas City and his long-term health. On the other hand, let's not forgot how dominant he's been since 2011, with a 2.71 ERA that ranks second among starting pitchers behind Clayton Kershaw and just ahead of Greinke. The Giants can dream on a repeat of his 2014 season in which he threw 243.2 innings and posted a 2.25 while leading the NL with 242 Ks. Of special note: He allowed 22 home runs that year, 16 in Cincinnati. Now he moves full-time into a pitcher's park that limits home runs. (Of course, so does Kansas City and that didn't help him.)

The impact: The San Francisco rotation:

Madison Bumgarner

Johnny Cueto

Jeff Samardzija

Jake Peavy

Chris Heston

Matt Cain

If Cueto is healthy ... if Samardzija bounces back to his 2014 form ... if Peavy can make more than 19 starts ... if Heston's first half is legit ... if Cain give you anything ... OK, that's a lot of "ifs." Still, it's a better rotation. Remember, in 2015, Vogelsong posted a 4.67 ERA, Hudson a 4.44 ERA, Lincecum a 4.13 ERA, Cain a 5.79 ERA. You have to like the chances for some improvement over that group with Cueto and Samardzija working with Dave Righetti and going to AT&T, and there's huge potential if Cueto and Samardzija max out.

Also: The Dodgers didn't get Greinke, they didn't get Price, they didn't get Cueto or Jordan Zimmermann. That's good for the Giants as well.

Look, I'd be worried about Cueto's elbow. He's also missed time with other non-arm injuries in the past. The best-case scenario for the Giants may be that Cueto is great and healthy for two seasons and then opts out. Keep in mind as well that none of the big-money contracts the Giants have given have worked out: Barry Zito was mostly a flop (although he came up big in the 2012 postseason), Cain got injured, Lincecum delivered minus-0.4 WAR over the two years of his $35 million extension. (The Bumgarner contract that included several team options was basically of no risk to the Giants, so I don't count that as a big-money investment.)

So maybe the Giants are due. They're betting $130 million that's the case. Hey, it's just money.