You know who really loves the Troy Tulowitzki trade? Josh Donaldson. Since Tulowitzki played his first game for the Toronto Blue Jays, Donaldson -- batting behind Tulo in the lineup -- has been on fire, hitting .353/.480/.863 with seven home runs, five doubles and 15 RBIs in 13 games. This hot streak has suddenly turned the American League MVP race into a two-way battle between Donaldson and Mike Trout:

Donaldson: .294/.362/.572, 31 HR, 83 RBI, 82 R, +9 Defensive Runs Saved, 6.2 WAR

Trout: .301/.394/.605, 33 HR, 69 RBI, 78 R, +3 Defensive Runs Saved, 7.0 WAR

The WAR number is closer at FanGraphs, where Trout leads 6.5 to 6.2. Before we dig deeper into the debate, let's take a quick look at Donaldson. Obviously, his power numbers are up this year as he's already set a career high in home runs. This is a reflection of moving to the Rogers Centre:

Road numbers

2013: .309/.400/.477

2014: .276/.361/.513

2015: .246/.332/.450

Home numbers

2013: .293/.367/.520

2014: .233/.322/.395

2015: .338/.391/.684

In 2013-14 at Oakland, he hit a home run on 10.4 percent of his fly balls. With Toronto, that number has increased to 16.4 percent. So while he hit 24 home runs in Oakland over two seasons, he's hit 20 at home this year. So Donaldson isn't really doing anything different at the plate; he's just playing in a better hitter's park. In fact, his strikeout and walk rates are both slightly worse than in his 2013 breakout campaign. He hit .255 last season due to a lot of bad luck on balls in play and an oddly low rate of line drives.

Back in May, ESPN Insider Tony Blengino addressed this in a piece headlined "Your 2015 AL MVP: Josh Donaldson." Good job, Tony. Basically, he projected Donaldson's line-drive rate to normalize and, helped by the park, his numbers to spike. Tony wrote:

"Each year I compile my own park factors based on batted-ball data. In 2014, Rogers Centre had the fourth-highest fly ball park factor (134.8), the third-highest line drive park factor (108.4) and the third-highest overall (114.7). It also had the fourth-highest home run park factor (127) and second-highest doubles factor (119). Rogers Centre is one of the few major league parks where a line drive can turn into a home run, especially to left and left-center field."

Bottom line: This park is tailor-made for Donaldson.

Overall, Donaldson has crushed fastballs this year, hitting .319/.398/.644 with 19 of his 31 home runs. Look at his heat map and you can see he loves that low and inside fastball -- the perfect pitch to drive to left and left-center:

ESPN

Now, park effects are built into WAR, which is why we pay attention to that figure alongside the raw numbers. Who has the advantage right now? Trout has the edge in WAR but Donaldson leads the AL in both runs and RBIs. That doesn't mean he's a lock for MVP if that keeps up; Curtis Granderson did that with the Yankees in 2011 and finished just fourth in the MVP voting. But it's certainly a plus on Donaldson's ledger, since not all voters are so inclined to consider WAR or properly consider park effects.

A few other issues that will arise, assuming both guys remain close statistically:

Playoff or no playoffs: If either the Angels or Blue Jays fall out of the playoffs, the helps the other guy. MVP voters always break close debates with the guy who made the playoffs (see Miguel Cabrera over Trout in 2012 and 2013, or Ryan Braun over Matt Kemp, or Joey Votto over Albert Pujols and so on).

He's carried the team: You see this one a lot. If you have bad teammates, that can hurt you (if you miss the playoffs) or help you (if you make the playoffs but it makes it appear you carried more of the load). This could help Trout, since the lineup around him isn't as deep as the one Donaldson has.

Defense: Trout's defensive metrics are much improved this year, from -9 defensive runs saved in both 2013 and 2014 to that +3 figure this year. But Donaldson is considered an elite defensive third baseman. Edge to Donaldson.

Baserunning: Trout doesn't run like he did his first two seasons, and has just 10 steals compared to Donaldson's four. Overall, Baseball-Reference.com credits Donaldson with two runs gained from his baserunning versus one for Trout, so neither has the advantage here (although the perception is likely that Trout adds more value from his speed, even if that hasn't been the case).

Clutch factor: We can look at a couple of different numbers here. Win probability added looks at when a hitter does his damage based on how much his team's chances of winning or losing the game change based on the outcome of each plate appearances. Donaldson has the slight edge here, with 4.0 WPA to 3.8 for Trout. (They're second and third in the AL, behind Nelson Cruz's 4.9). Baseball-Reference.com tracks high-leverage, medium-leverage and low-leverage situations, based on the score. Both have been clutch in high-leverage situations: Donaldson hitting .366/.448/.704, Trout hitting .344/.446/.721. So no edge to either player here.

Newness factor: Voters don't like giving the MVP Award to the same player every year. Willie Mays could have won nine or 10 MVPs, but won just two. Barry Bonds won seven but led NL position players in WAR 11 times. So this could help Donaldson, since Trout won last year.

Best player in the game: Maybe we're overthinking everything. Edge here to Trout.

Stretch run: If I had to predict, considering both teams will likely be fighting for a division title, the guy who has a big series or game-winning hit in a crucial game to create that moment to remember wins the award. It's obviously a little ridiculous to overemphasis one game or series, but this helped push Chipper Jones over the top in 1999 when he destroyed the Mets in a crucial September series, or Buster Posey in 2012 when he hit .364 in September. So, yes, for all the numbers we can digest, it may come down to one walk-off home run in a game against the Yankees or Astros that decides your AL MVP.