What's the best infield combo in the Majors?

When players like Nolan Arenado start coming up in trade buzz, you can't help but ask: How could a team possibly trade away a generational superstar?

Oh, and for the Rockies right now, there's also this: How could you break up MLB's top infield duo?

Yes, that's right -- Arenado and Trevor Story are the best partnership on any diamond in baseball entering 2020. Here's why: Even among all the star tandems around the Major Leagues, Arenado and Story's combination of elite defense and elite offense stands out.

Start with the glovework. Infielders come in twos -- the left side, the right side, the corners, the middle. The left side in Colorado is unmatched.

With Statcast's new Outs Above Average metric for infield defense, we can see which teams had the most valuable pairings last season. Arenado and Story are the clear No. 1.

Together, Arenado and Story were worth +32 Outs Above Average in 2019. Arenado was +17 at third base. Story was +15 at shortstop.

Best current defensive infield duos
By combined 2019 Outs Above Average
1) Nolan Arenado +17 / Trevor Story +15 (Rockies 3B/SS): +32
2) Matt Chapman +14 / Matt Olson +12 (A's 3B/1B): +26
3) Nick Ahmed +16 / Christian Walker +9 (D-backs SS/1B): +25
4) Paul DeJong +13 / Kolten Wong +10 (Cardinals SS/2B): +23
5) Javier Báez +19 / Kris Bryant +2 (Cubs SS/3B): +21

Check out how good they were at taking away half the field from opposing hitters. Here's a combined overlay of their Outs Above Average for 2019, based on their starting positions on every play they were responsible for. See all that red? Red means good.

Arenado and Story were both top-five infield defenders in the league overall. Arenado ranked second in OAA behind only Báez, and Story ranked fifth, with only Ahmed and Andrelton Simmons (+16) between the two Rockies teammates. The A's, with Chapman at No. 6 and Olson tied for No. 8, were the only other team with two top-10 infielders -- but Arenado and Story each outranked both Chapman and Olson

And if you look at the top duo at each infield "grouping" -- those left side, right side, up-the-middle and corners categories that fielders naturally fit into -- Arenado and Story manning the left side in Colorado were head and shoulders above anyone else.

St. Louis was the best on the right side -- Wong and Paul Goldschmidt (+5) combined for +15 OAA, less than half of Arenado and Story's total -- and up the middle with DeJong and Wong, whose +23 OAA still trailed Arenado and Story by a wide margin. The corners in Oakland were superb, but even the Gold Glovers Chapman and Olson ranked easily behind the Arenado-Story duo at +26 OAA.

All of this shouldn't be any surprise when it comes to Arenado, who's widely regarded as one of the best overall defenders in the sport. He's won seven straight Gold Glove Awards at third base to start his career, a Major League record for an infielder, and he's won the last three Platinum Gloves as the NL's best defender at any position.

But you might not have realized just how good Story was at short, a premium defensive position. He's not just a slugger.

Story is a slugger, though. And so is Arenado. Arenado and Story combined to hit 76 home runs in 2019 -- 41 by Arenado, 35 by Story. That was tied for the most of any pair of infield teammates last season.

Most HR by infield teammates in 2019
1-T) COL -- Nolan Arenado (41) / Trevor Story (35): 76
1-T) NYM -- Pete Alonso (53) / Jeff McNeil (23): 76
3) ATL -- Freddie Freeman (38) / Josh Donaldson (37): 75
4-T) HOU -- Alex Bregman (41) / José Altuve (31): 72
4-T) OAK -- Matt Chapman (36) / Matt Olson (36): 72

The two Rockies both reached the 35-homer mark; only Freeman and Donaldson and Chapman and Olson joined them in that category. Arenado and Story also both posted an OPS over .900 (Arenado .965, Story .917), one of six infield duos to do so -- Freeman and Donaldson for the Braves, Xander Bogaerts and Rafael Devers for the Red Sox, Bryant and Rizzo for the Cubs, Bregman and Altuve for the Astros, and Alonso and McNeil for the Mets were the others.

What makes Arenado and Story unlike nearly all the others, though, is their rare level of two-way superstardom. It's rare enough to have even one infielder like that on your team, let alone two. Arenado and Story have some close rivals in the Oakland Matts -- A's fans should enjoy watching every second of Chapman and Olson playing, and they're an amazing infield duo in their own right.

But right now, the Rockies have the best.