Nolan Arenado is an MVP candidate. Charlie Blackmon is an MVP candidate. But they both can’t be the MVP! (Well, technically it is possible; Keith Hernandez and Willie Stargell shared National League MVP honors in 1979.)

Before we determine if either is a strong contender for NL MVP, we have to first establish the MVP of the Colorado Rockies. Both are having superlative seasons as the Rockies try to hold on to the second wild card and make the playoffs for the first time since 2009. Arenado is closing in on his third straight RBI title and will undoubtedly win his fifth Gold Glove in five seasons, while Blackmon leads the majors in runs scored and total bases.

The numbers:

Arenado has a lot of RBIs -- but he has Blackmon hitting in front of him. Blackmon has a lot of runs -- but he has Arenado driving in him. On a rate basis, Blackmon has been the slightly better hitter, thanks to a 25-point advantage in on-base percentage.

Note the differences in WAR for each player. Those numbers are essentially the result of how each player’s defense is evaluated. Arenado rates better in Baseball-Reference WAR, which uses Defensive Runs Saved, in which he is plus-20 runs saved above average; FanGraphs WAR uses UZR, in which he rates at plus-7.4 runs. Likewise, Blackmon rates at minus-6 DRS but +0.1 UZR.

In Arenado’s case, I’m inclined to go with the DRS number, which is the highest among third basemen. He is second in UZR behind Anthony Rendon, though he rates just 10th in the range component of UZR. You think nine third basemen have more range than Arenado? Going with Baseball-Reference WAR certainly helps Arenado’s case. Still, there’s enough of a debate here to dig into some of the secondary numbers.

Let’s start with RBIs, because that’s going to be a big argument in Arenado’s favor. Although voters are getting smarter in their statistical analysis, some still love RBIs. But how much of Arenado’s RBI total is a function of his spot in the lineup? Baseball-Reference tracks runners on base for hitters compared to the MLB average given a player’s plate appearances. Arenado has had 409 runners on base compared to an average of 376; Blackmon has had 269 runners on base compared to an average of 399.

Subtracting home runs, Arenado has knocked in 22.2 percent of the runners on base for him; Blackmon has driven in 21.6 percent. Very close! Both have been terrific with runners in scoring position: Arenado is hitting .404/.483/.829 and Blackmon is hitting .368/.449/.689.

The interesting thing here is that Bud Black’s batting order is a little suboptimal. DJ LeMahieu basically hits singles; it would arguably make more sense to hit him leadoff and Blackmon second so that Blackmon would be hitting with more runners on base, rather than hitting after the No. 8 and 9 hitters.

OK, so as well as Arenado has hit with runners in scoring position, I don’t think RBIs separate him from Blackmon. Let’s go to clutch hitting. We can look at a couple different stats. Win Probability Added looks at when a player contributed his numbers; for example, a home run in a tie game is worth more than a home run in a 10-2 game. Both players rank high in FanGraphs’ WPA: Arenado is fifth among position players at 4.45 WPA, and Blackmon is seventh at 4.27. Not much to pick at there.

Let’s go to “Late & Close” situations:

Arenado: .246/.315/.600, 6 HRs, 19 RBIs in 74 PAs

Blackmon: .269/.372/.463, 3 HRs, 10 RBIs in 78 PAs

The edge here goes to Arenado. He hit the most memorable home run of the season for the Rockies, a walk-off, three-run homer to beat the Giants 7-5 on June 18, a blast that not only won the game but also completed a cycle:

Arenado also hit a go-ahead home run in the ninth inning to beat the Brewers 2-1 on April 6 and a three-run homer off Arizona’s Jake Barrett in the eighth inning on Sept. 11 to break a 2-2 tie. And don’t forget the three-run homer off Clayton Kershaw in the first inning Sept. 7. The Rockies entered the four-game series at Dodger Stadium reeling, with a playoff spot that once seemed secure in jeopardy. Arenado’s home run kick-started a 9-1 victory and four-game series sweep.

Not to ignore Blackmon, who has had a couple huge home runs as well. He homered off Cleveland's Zach McAllister in the top of the 12th on Aug. 9 to give the Rockies a 3-2 win. Later in the month, he clocked a two-run shot off the Braves' Arodys Vizcaino in the top of the ninth for a 6-4 lead (the Rockies won 7-6).

Finally, let’s see how the two players have done against the Dodgers and Diamondbacks, their key rivals in the NL this year:

Arenado: .310/.387/.611, 8 HRs, 28 RBIs, 22 runs

Blackmon: .294/.360/.463, 4 HRs, 13 RBIs, 21 runs

Arenado has done some of his best hitting against the two teams the Rockies most needed to beat.

Finally, there’s the matter of home/road splits. Arenado has hit .289/.359/.543 on the road compared to Blackmon’s .283/.339/.453. You can’t simply compare the splits and say Arenado is better because he doesn’t have as severe a split as Blackmon (who has hit .387 and slugged .784 at home). You can turn that around and ask why Arenado hasn’t hit better at the most hitter-friendly park in the majors. Still, for those who want to use Coors Field against Rockies players, that argument has less weight for Arenado since he has fared well on the road.

Add it up, and I have to give the slight edge to Arenado. He has fared better in the areas WAR doesn’t capture, such as clutch hitting and playing well against your toughest opponents. I don’t know if Arenado is the National League MVP, but he’s my choice -- with two weeks remaining -- for Rockies MVP.