SAN DIEGO -- In the Padres' efforts to build toward contention in 2020, their most pressing concern is the starting rotation. They're deep in numbers and deep in prospects. But they're severely lacking in proven big league talent.

As a result, general manager A.J. Preller is actively searching for established arms who can help the club beyond 2019. It's why he took a risk on Garrett Richards coming off Tommy John surgery. And it's why he's exploring trades and free agency in an effort to add to the team's rotation of the future.

From all that, a surprising name has emerged among San Diego's offseason targets. The Padres have indeed spoken with the Yankees about Sonny Gray , as MLB.com's Jon Paul Morosi reported. There's no indication that a deal is particularly close, but it's a possibility.

That doesn't exactly fit the plan. Gray is slated to become a free agent next offseason, and he's owed a raise from his 2018 salary of $6.5 million in arbitration. The Padres, of course, would like to see major improvement on their disappointing '18 campaign. But they've repeatedly said they won't sacrifice the future to do so.

Then why explore this trade? Well, the organization doesn't view a potential Gray deal as counterintuitive to those stated goals. There are a few factors to take into consideration:

What's the cost?

For parts of five seasons, Gray was an extremely effective starter in Oakland. He made 112 starts there and posted a 3.42 ERA.

It's been a while since we've seen that version of Gray. Before he was demoted from the Yankees' rotation in August, Gray owned a 5.56 ERA in 21 starts. Earlier this offseason, general manager Brian Cashman made it very clear that Gray's time in New York is over.

All of that's to say: Gray's trade value isn't particularly high. The Padres have the deepest farm system in baseball, and if they part with a low- to mid-level prospect or two, it would hardly put a dent in their future.

Could they buy low and sell high?

The Padres' interest in Gray comes from the hope that pitching coach Darren Balsley can help rekindle Gray's All-Star-caliber form of 2014 and '15.

If that version reappears, Gray would be the best pitcher on staff and a valuable innings eater. More importantly, however, he'd be a chip. A revitalized Gray could prove valuable to a contender at the Trade Deadline. In theory, the Padres could flip Gray in July for more than what they would pay for him in December.

If they don't, Gray's performance could still earn him a qualifying offer. He could turn it down, and the Padres would get compensation in the 2020 Draft. Or he could accept, and the Padres would have a useful rotation piece on hand for one more year.

What's the upside?

It's easy to draw comparisons to a similar deal that Preller made last December, when he acquired Freddy Galvis from the Phillies for pitching prospect Enyel De Los Santos . Galvis was solid at shortstop all season. But now he's a free agent. The return on that investment is essentially over.

The organization views Gray as a different kind of risk. A year ago, it was pretty clear what value Galvis would bring in 2018. He's been the model of consistency, and he started 162 games last season with numbers that were, frankly, entirely predictable.

Gray sits on the opposite end of the spectrum. No one can say definitively what kind of pitcher he'll be in 2019. With a change of leagues and a change of scenery, he could revert to his All-Star form. If so, the Padres would get a nice return on their investment.

Or he could be a dud, and San Diego will have parted with Minor League resources for a commodity that won't help at all beyond 2019.

Is that kind of volatility worth the cost? And perhaps most importantly: What, exactly, is a reasonable cost?

The Padres are asking themselves those exact questions right now.