The player who might be most in demand at the trade deadline is a 2017 All-Star, but he could be the most obscure one. San Diego Padres reliever Brad Hand is a 27-year-old left-hander with four career saves, but every playoff contender looking for a bullpen upgrade -- which is pretty much every playoff contender -- will be calling the Padres.

Over the past two seasons, Hand is tied with Chris Devenski for most innings pitched among relievers. He’s third in strikeouts and eighth in WAR. Among relievers with at least 80 innings pitched, he ranks in the top 20 in strikeout rate, OPS allowed and weighted on-base average (wOBA) allowed. He has been effective against righties and lefties. Given his workload, he has been one of the top-10 relievers in the game -- sort of an Andrew Miller lite.

Amazingly, the Padres claimed him off waivers in April 2016 from the Marlins, who grew frustrated with Hand’s inability to develop into a starter. Still, it’s hard to believe an organization as talent-starved as the Marlins would give up on a former top prospect without giving him a longer run as a reliever. The Padres immediately put Hand in the bullpen. Like Miller, he became primarily a fastball/slider pitcher. His fastball still sits around 92-94 mph, and the slider is his wipeout pitch, with batters hitting .114 against it with a 50 percent strikeout rate.

As with Miller, it's Hand's abilities to retire batters from both sides of the plate and go more than three outs at a time that make him so desirable to playoff teams. He has gone four or more outs in 11 of his 39 appearances this year and is on pace to pitch in 78 games, the kind of durability managers will want in October.

Remember how Joe Maddon and Terry Francona managed their pitching staffs in October: quick hooks on their starters and then riding Aroldis Chapman and Miller, respectively, for more than three outs. Cubs starters pitched seven innings just three times in 17 postseason games and went fewer than five innings five times even though the starters didn't give up more than three runs in those games. Indians starters went seven innings just one time and fewer than five eight times in 15 games. Given that offense is up across the majors this year, teams are likely to demand even more from their bullpens this postseason.

Why would the Padres trade Hand, who isn’t a free agent until after 2019? Simple: A rebuilding team should always cash in on a reliever when it can. The Padres might not be good until 2019, about when Hand will be ready to leave the team as a free agent. He could get hurt or lose effectiveness before then, too, and San Diego also has two other decent southpaws in Ryan Buchter and rookie Jose Torres.

Here’s a quick look at the leading playoff contenders, ranked in order of most likely to acquire Hand:

Washington Nationals: Of course. They have an MLB-worst 5.19 bullpen ERA, and Hand would immediately become their best reliever, whether as a potential closer or setup guy. Really, the Nationals should acquire at least two relievers. Hand and a closer such as David Robertson would certainly help Dusty Baker’s heart. While you’ll hear that teams will hold the Nationals hostage in trade talks, that’s not necessarily true: The Nationals just have to make a better offer than anybody else.

Milwaukee Brewers: The Brewers absolutely should be buyers, and the biggest need they have is upgrading the bullpen. All-Star Corey Knebel has locked down the ninth inning since taking over as closer, but the pen still ranks 16th in ERA. The Brewers have a deep farm system to make a deal, and having team control over Hand for two more seasons means he still fits into their long-term plans. Plus, Hand has more value to a division winner than to a wild-card team that could be one-and-done.

Los Angeles Dodgers: They have the second-best bullpen ERA behind the Indians, but the two lefties are Luis Avilan and Grant Dayton, and neither is extremely trustworthy. Pedro Baez has been the eighth-inning guy, and he has a 1.26 ERA but hasn’t really been as dominant as the ERA suggests, with 15 walks in 35⅔ innings -- including a 10/9 SO/BB ratio versus left-handed batters. You don’t really want him facing a string of lefties with the game on the line. Remember, Dave Roberts had problems last October bridging the gap from the starters to Kenley Jansen. Hand would give him much more versatility in that area.

Boston Red Sox: As with the Dodgers, the bullpen has been solid, ranking third in the majors in ERA. Joe Kelly is currently riding a 23-game scoreless streak to emerge as a key weapon behind Craig Kimbrel. As with the Dodgers, however, there isn’t a dominant lefty in the pen, and you can never have too much depth. Plus, we know Dave Dombrowski has tried to upgrade his bullpen since taking over the front office, acquiring Kimbrel, Carson Smith and Tyler Thornburg. Smith and Thornburg immediately got injured, so Hand could fill the role they originally expected from Thornburg.

New York Yankees: Chapman and Dellin Betances have had a couple of hiccups lately, but they should be fine. Chad Green has supplanted Tyler Clippard as the No. 3 guy, but given that Yankees starters don’t go very deep into games, adding Hand would allow Joe Girardi to have even quicker hooks with his starters.

Arizona Diamondbacks/Colorado Rockies: The Arizona bullpen ranks a surprising fifth in ERA, and the Colorado pen has faded of late, other than closer Greg Holland. With the Dodgers a heavy favorite to win that division, however, it seems unlikely either would be the high bidder. If the Rockies do swing a major trade, it’s more likely to be for a starting pitcher (although it’s really the offense that needs some help).

Houston Astros: They’re only 13th in bullpen ERA, and their top guys are all right-handed (Tony Sipp is the one lefty), but all indications are that they’d prefer to add a starter over a reliever.

Cleveland Indians: They still have Miller, closer Cody Allen and Bryan Shaw, and Zach McAllister is having a strong season. Given the steep price they paid to get Miller last season, though, and given their bullpen's MLB-best 2.80 ERA, they probably won’t be dealing prospects again for bullpen help.