The Giants want Matt Cain to win the fifth starter’s job in spring training. This was a logical guess at the start of the offseason, it was the logical guess a couple weeks ago, and it’s a confirmed position now. From a Reddit AMA with GM Bobby Evans:

(Ty Blach’s chances of starting) really depends on the performance of other guys in camp, particularly Matt Cain. Our hope is that Matt takes that 5th spot, but Blach is a good option otherwise.

This is for a lot of reasons, I’m assuming. First, Cain is the only one of the two with extensive major league success, even if that came years and years ago. Second, Cain is the 30th-highest paid player in baseball, making $750,001 more than Mike Trout, and it would be nice to get some value back. Third, if Cain isn’t in the rotation, the Giants would have to put him in the bullpen, because we know they aren’t releasing him, and no one knows if that role would be a good fit.

Fourth, because some of us are silly dreamers who blame the four years of sub-standard performances on four years of injuries. “This is the year,” us morons exclaim, just like we did for year after year with Tim Lincecum. “This is totally the year.” I apologize in advance for my part in this.

The question now, then, is what this spring battle will look like. How will we tell who is winning? Before you answer with something snarky, consider the following:

1. Matt Cain’s fastball velocity isn’t a measure of success

Cain’s fastball velocity was at a career low last year, but not by too much. The last time he averaged anything higher than 91.5 mph was in 2009, so it’s not as if the Giants can watch radar guns in March and proclaim that the old Cain is back. If he’s throwing 91 or 92, that’s great, but he has been for the last four years, so it’s not really telling us anything.

2. Just about every bad outing can be reduced to “It’s spring”

Every single one.

“He was working on his (curveball command/delivery/fastball location/tennis-like grunting) more than anything, so you can’t really judge this outing based on results. We were happy with a lot of what he did out there.”

And you know what? That doesn’t have to be a lie. There are a lot of reasons for a pitcher to approach an exhibition game differently. There are reasons for pitchers to focus on a specific pitch and become predictable. Johnny Cueto had a 9.58 ERA in three spring starts last year. Madison Bumgarner was even worse. Why?

Dunno. They were rusty and/or worried more about granular improvements to their delivery or repertoire than they were about their ERA. That’s spring, ha ha. It means nothing. Except when you’re counting on it to make a decision.

It’s possible for Cain to give up 48 earned runs in four outings and still win the job. Depends on how he looks out there to Dave Righetti and the rest of the brain trust.

3. Cain looked good early in games last year

It wasn’t just your imagination.

Matt Cain’s progressive struggles Times through lineup PA HR BB SO BA OBP SLG OPS Times through lineup PA HR BB SO BA OBP SLG OPS 1st time through lineup 150 4 13 29 .241 .318 .376 .694 2nd time through lineup 139 6 12 24 .316 .396 .521 .917 3rd time through lineup 84 6 6 12 .411 .434 .781 1.215

Cain would be cruising, only to hit a nasty pothole the second or third time through the orders. It was entirely predictable. And guess what spring training is all about? Going through the order once. More toward the end of spring, but it’s not like you see a lot of complete games in March.

If Cain is successful in the spring, it would be hard to tell if he’s really more effective than he was last year, because he was pretty danged effective his first time through the order in 2016, too. The real test comes with exactly what pitchers aren’t expected to do in spring training.

All of these points can be reduced to the same problem: It’s hard to glean too much information from spring training results because we’re all too smart to glean too much information from spring training results. It’s not like the Giants were quietly working the phones last March, looking to sell high on Madison Bumgarner when his ERA was in the 10s.

Based on the Giants’ own words, then, I’ll guess that Cain has about a 95-percent chance of opening the season as the fifth starter. If he struggles in the Cactus League? It’s just spring. His velocity is where it was last year. He was working on things, so you can’t pay attention to the results. He’ll need to fail in a dramatically obvious way, with Blach succeeding in a dramatically obvious way. If Cain isn’t the fifth starter, it’ll be because his struggles were painful and startling in a way they weren’t last year. HIs 2016 campaign was filled with “I don’t get it. The stuff looks fine.” If he does the same thing in the spring, that’ll be tweaked to “Don’t worry about it. The stuff looks fine.”

This isn’t to say that it will be the wrong decision, mind you. The Giants might be correct in their evaluations, and Cain might end up being the better choice after all. This is just a quick note, though, that the battle probably won’t be much of a battle. Once a team has designated a front-runner in a position battle, it’s hard for another player to pass him with the help of exhibition games.

Cain is that front-runner. The team wants him to win the job. And it’s going to take a complete meltdown to prevent him from winning it. Adjust your expectations accordingly.