The Colorado Rockies completed a sweep of the Giants on Wednesday with a 4-2 win. The big blow was Nolan Arenado's three-run homer in the first off Tim Lincecum. Jough Brasch of the Rockies Zingers blog has a recap of the series here, pointing out that the Rockies have gotten off to good or decent starts in recent years, then usually falter in May.

The Rockies are 6-0 on the road, and that's a big deal for a club that went 21-60 on the road last year, eight fewer wins than the second-worst road team, the Padres. The Rockies usually have one of the largest home/road splits in the majors. Check out their edge at home over the past decade:

2014: +24 wins

2013: +16

2012: +6

2011: +3

2010: +21

2009: +10

2008: +12

2007: +12

2006: +12

2005: +13

It's no coincidence that the Colorado playoff teams in 2009 and 2007 were decent on the road, winning 41 and 39 games, respectively.

What's interesting is that last year the Rockies won eight road games in April -- then only 13 the rest of the season. In 2013, they went 7-8 on the road in April and 22-44 the rest of the season. In 2012, it was 4-5 in April and 25-47 after that. In 2011, 10-3 in April, 25-43 from May 1 on. Maybe this all just coincidence. Or maybe it's a trend.

The Coors Field factor isn't so much winning at altitude; it's winning on the road. Rockies hitters die when they get away from Coors. But whatever causes that effect -- most likely, after seeing fewer good breaking balls at Coors, it becomes harder to hit them on the road -- perhaps takes some time before it exacts its toll. The Rockies leave spring training like any other team and perform well in April (or decently, given whatever talent level on the team), then as they get further from spring training, the Coors effect builds. That's my theory anyway.

So let's see if that's case, comparing how the Rockies hit on the road in April versus the rest of the season.

2014

April: .254/.302/.403

Rest of season: .222/.272/.375

2013

April: .273/.343/.447

Rest of season: .240/.287/.356

2012

April: .211/.268/.352

Rest of season: .244/.294/.373

2011

April: .229/.321/.381

Rest of season: .245/.307/.372

2010

April: .256/.313/.426

Rest of season: .222/.301/.340

So there seems to be something going on here. They were worse in April in 2012, but that was a small sample size of just nine road games. Of course, there are other potential factors in play here. Troy Tulowitzki and Carlos Gonzalez, for example, are usually healthy in April and get hurt at some point. (That sounds good, except the Rockies haven't had the same drop in offense at home after April.) Maybe playing at altitude just creates more fatigue. Indeed, over the past five seasons, the Rockies have played .623 at home in April and .515 at home from May 1 on.

I'm not sure there's a solution here. The Rockies probably need to rest their regulars more than other teams, maybe invest in a larger training staff that helps with conditioning at altitude. If there's a better way to replicate sea-level batting practice, figure that out as well. The Rockies have probably thought of all this stuff. Anyway, they have proved they can succeed, which gets to the ultimate question: Is this just a hot start or are the 2015 Rockies a better team than everyone predicted?

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