The Texas Rangers put a cherry on top of their lineup on Saturday in the form of Shin-Soo Choo. They’ll be paying Choo $130 million over the next seven years, which is indeed a substantial amount of dough for a player who’s on the wrong side of 30. But, in a sense, it was a necessary move for the Rangers.

We know the story with Choo: He’s an on-base machine. Just three players topped his .423 OBP last year, and if you put that together with a handful of other factors, you wind up with the ninth-best park-adjusted hitter in baseball. If you prefer wOBA, Choo ranked 11th. And if you prefer fWAR, he ranked 20th. Hence the reason he just signed a $130 million contract.

Even if you think $130 million is an overpayment, look at the deal from the Rangers perspective: Choo is a considerable short term upgrade over Michael Choice, who was slotted to enter Spring Training with a firm grip on left field.

Now, it’s tough to draw any huge conclusions about Choice, given that he recorded just 19 at-bats at the major league level last year. Sure, he was well below average in those 19 at-bats, but that is essentially meaningless. He’s 24 and had a handful of monster seasons in the minor leagues (if you like to make conclusions off minor league stats) but all signs point to Choice as an inferior player for the immediate future. Maybe Choice would’ve blossomed into a competent everyday left fielder, but it's possible that he was going to need seasoning. With Choo now in the fold, that speculation is moot and Choice can ease into a big league job.

And that’s good news for a Rangers outfield that struggled in 2013 after dominating in 2012 (more on that in a minute).

Year wRC+ wOBA ISO 2013 99 (16th) .327 (10th) .166 (5th) 2012 120 (5th) .356 (2nd) .206 (2nd)

*MLB Ranks

You’ll notice that the Rangers outfield wasn’t starved for power in 2013 (or 2012, for that matter), boasting baseball’s fifth-highest outfield ISO. Most of that can be chalked up to Cruz’s .240 ISO. So replacing Cruz with Choo (.178 ISO in 2013) most likely isn’t going to benefit the Rangers in the power department.

Even given the power factor, the Rangers outfield trended downward in 2013, and I think you can guess where it started: Josh Hamilton’s departure, combined with David Murphy’s decline. Hamilton would’ve been expensive to retain and even if letting him walk was the right move, the Rangers haven’t come close to replacing his offensive production in the outfield. A similar situation--obviously not as dramatic--would’ve surfaced had Cruz bolted and without the Rangers countering, which would've left them with an outfield of Choice, Leonys Martin and Alex Rios. Offensively, the Rangers outfield looked like a problem.

We know that swapping out Cruz for Choo will cost the Rangers some pop, but it isn’t terribly significant when you factor in what Choo will bring to Texas’ leadoff spot--typical leadoff hitter things, highlighted by a fantastic OBP that we’ve already drooled over enough.

The Rangers already had a capable leadoff hitter in Ian Kinsler. They finished 2013 eighth in OBP out of the leadoff spot, with Kinsler getting the lion’s share of at-bats at the top of the order. Of course, he was the key piece in the swap that netted Texas Prince Fielder, so he’s out of the mix.

That meant the Rangers would have had to choose among Elvis Andrus, Leonys Martin and Jurickson Profar to fill the void. Those are some intriguing and competent names, sure, but Choo is superior for now. Among leadoff hitters who totaled at least 300 plate appearances in 2013, Choo’s .432 OBP led baseball. Kinsler’s .355 OBP was fifth. Translation: Texas goes from very good out of the leadoff spot to league-best. If you’re going to make an upgrade, that’s the a good way to proceed.

The overlooked benefit of Choo taking over the leadoff duties is that Texas’ lineup becomes much more dynamic, as Martin and Profar both slide down to the No. 8 and No. 9 spots, which can generate even more traffic on the bases in front of the middle of the order. Let’s just say that there will be plenty of ducks on the pond.

Of course, Choo, and his seven-year pact, don’t come without flaws.

For Choo, the big one is his inability to hit southpaws. You’re probably not hearing about it for the first time either, and it’s no wonder why, as Choo slugged a mere .265 against lefties, 39th-worst in baseball in 2013. Perhaps, if this was just a one-year trend, we wouldn’t dwell on it so much. We’d wait another year for a larger sample size and be done with it. But neither of those two options are available--Choo has slugged .341 against lefties over his nine-year career.

Aside from that, Choo’s walk and strikeout percentages could stand to regress a bit. Normally, Choo’s K% falls in the 20% range. Just once before 2013 did he finish a season with a K% south of 20% (not including his rookie season in which he collected just 21 plate appearances). 2013 saw him do that for a second time.

Choo entered 2013 having never posted a BB% north of 13% in a single season and 2013 was a first in that department as well. Additionally, Choo generated 53.4 runs above average against fastballs (wFB), a mark that surpassed his previous career-best of 26.9 runs. I’d say it’d be wise to pencil him in for some regression against fastballs, given that pitchers will adjust accordingly. We can also chalk some of the change up to switching leagues, but he's heading back to the AL.

We are nitpicking to some extent here, given that Choo was a good player before 2013. Still, it’s necessary nitpicking, because without walks, Choo’s OBP dips. With more strikeouts, there aren’t as many opportunities to get on base via balls in play. Without as much success against heaters, he gets fewer hits, barring an adjustment on his part. It all connects into one big picture.

As for the deal itself, $130 million is a lot of money. It’s not, however, a contract that Choo can’t make worthwhile. The current price of one win is about $6 million on the free agent market, so Choo will have to be worth approximately 22 wins over the life of the deal, or roughly three a year, which is easily doable. If the price of a win continues to increase over the life of the deal, then he might not even need that many.

Below are Oliver’s fWAR projections for Choo through 2018. Since that covers five of the seven years, I subtracted 0.5 wins from each of the following two years.

Year Proj. fWAR 2014 4.7 2015 4.5 2016 4.1 2017 3.7 2018 3.4 2019 2.9 2010 2.4 Total 25.7

With nearly 26 wins, Choo would easily surpass the 22-win total he needs to earn his $130 milliom. I advise you not to be too stubborn with the 22-win total given that the value of a win is a moving target. Even a 5% inflation would bring Choo’s target down to the 18-win level, and 5% might be conservative. It's a bit hard to be sure given the influx of money into the game.

Beyond that, Oliver assumes that Choo will reach the 600 plate appearances mark in each season. That’s not a guarantee for anyone and a glance over Choo’s Baseball Prospectus’ injury page shows us that he does have a bit of an injury history too.

On the surface, $130 million seems like a lot of money for a corner outfielder who is over 30 and carries a sizable platoon split, but he's projected to age reasonably well. We shouldn't blindly trust the projections, but unless Choo falls apart quickly, the Rangers shouldn't be left holding a terrible deal.

Choo makes the Rangers better, and as far as position players were concerned, he was really the only player left who could significantly improve their roster. Given where they sit on the win curve and the competition they have to face, the Rangers have a lot to gain from signing Choo, even if it doesn't turn out to be the best investment over the course of the entire deal. The potential short-term value is enormous, as Choo's ability to get on base in front of the Beltre and Fielder could be the difference between another early exit and a run deep into October.

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All statistics courtesy of FanGraphs and Baseball-Reference

Jake Dal Porto is a writer at Beyond The Box Score and Golden Gate Sports. You can follow him on Twitter @TheJakeMan24.