Yu Darvish was not at his best Sunday night.

His fastball, as it occasionally is, was willful when he tried to command it. He gave back two early one-run leads. He exited after five innings a day after the Rangers maxed out their long reliever. It was, quite frankly, about as badly as he has pitched this season.

I've seen enough.

Offer the man a contract, already.

Even when he's been "bad," he's found a way to pitch effectively.

If I'm Jon Daniels, I'm ready to offer him a contract right here and now. Or at least negotiate to my best offer over the next six weeks. If the Rangers are serious about extending their window of contention past this year and bridge until the next wave of pitching talent arrives from the minors -- if it arrives at all -- making serious runs at both Darvish and his Japanese bestie, Shohei Otani, are the best and most cost-effective routes to ensure the window doesn't close any time soon.

More on Otani in a minute, but first things first: Darvish. His next start, at Toronto this weekend, will be his last in the 12-month period since he returned from Tommy John surgery. With almost every outing, Darvish seems to be getting better. Consider a 3.18 ERA, 10th best in baseball, over 27 starts since his return last May.

In categories such as ERA, opponents' on-base percentage and fielding-independent pitching, he ranks among the top four in Rangers history for the course of his career. The only pitchers he trails are Hall of Famers. Either you believe the stats and he's as good as the Rangers have ever had, or you believe a baseless narrative that he "lacks a will to win." Physically, I believe he's an outlier, more likely to carry his "prime" past prime time.

The question you are clearly asking yourself: How much of Ray Davis' money, which isn't mine to spend, am I willing to pretend to spend?

Said with my best Dr. Evil grin: $155 million.

For starters.

The best market comparison for Darvish is probably Stephen Strasburg, who got $175 million over seven years from Washington last spring. It features two opt-out clauses in the middle. It will serve as our model. Strasburg, like Darvish, has had Tommy John surgery and only one 200-inning season to his credit. Biggest difference: Strasburg is two years younger, which is why our Darvish deal is for six years, to account for the difference in age and potential effectiveness at the end of the contract.

Like the Strasburg deal, we will also make the middle years of this $26 million-per-year deal the biggest paydays. They will be timed to coincide with increased revenues from a new stadium set to open in 2020 and his opt-out clause. Meaning: If he opts out after, say, Year 3, he'll be giving up a $30 million-$35 million salary for 2021.

If you are the Rangers, you do all this to keep Darvish, but also to lure Otani, who figures to be something of a bargain thanks to new regulations in the posting and international bonus system that will probably limit a six-year investment in him to about $60 million.

The posting system for Japanese players now maxes out at a $20 million ceiling. Because Otani, who turns 23 in July, is still under the age of 25, he is subject to the international bonus pool limits. Tops for that is $5.75 million (the Rangers have a $4.75 million pool), though teams can acquire some extra slots to increase their available bonus pool by up to 75 percent. Even if a team with the biggest pool acquired the maximum number of extra slots, it couldn't go above $10.1 million. The players must sign minor league contracts with strict governance on salaries.

The biggest "loophole" would be to have a handshake agreement on a long-term major league deal. The top of the market for that is the six-year, $25 million deal Tim Anderson signed with the Chicago White Sox earlier this year. Probably can't go much above $30 million there. Max: $60 million investment.

So, you'd potentially be looking at a big field offering relatively similar financial packages. Otani's decision may come down to where he wants to live and with whom he wants to pitch. In a lot of ways, it's going to be like a college recruiting process.

And this is how Darvish -- and to another extent the commitment put in to making an impact in Japan by assistant general manager Josh Boyd -- could potentially be the biggest assets the Rangers have in separating themselves from the field. Otani and Darvish are close. They are offseason workout partners. Darvish speaks highly of Texas. It would create as seamless a transition to the majors as possible for Otani.

This whole package would potentially cost the Rangers something like $200 million. They paid $107 million for Darvish in 2012. The thought they could get the equivalent of two Darvishes for the same average investment some five years later makes it a bargain the Rangers must pursue.

Twitter: @EvanPGrant

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