According to Dan Hayes of The Athletic, the team hopes for a minimum stay on the injured list. Given the early date on the calendar and the cold weather in which the team will continue to work for several weeks, they have to err on the side of caution.

Maybe, if this were a later stage of the season, we would even see López remain active and miss just one start.

However, while the strain is mild, even such minor variations of this injury can flare up or heal more slowly than expected.

I analyzed all hamstring strains with which big-league pitchers have missed time since the start of the 2016 season, when Baseball Prospectus’s Return to Play Dashboard begins.

There have been 126 such documented cases, and because the implications might be supposed to be different for the processes of both recovery and performance, I broke them down by whether the injury was to a hurler’s push-off leg (the same one as the hand with which they throw) or their landing leg.

Here’s a snapshot of some of those injuries, with the most severe cases filtered out for the purposes of estimating the likely timeline on a return.

I found that injuries to a pitcher’s push-off leg (like López’s) are notably less common.

There were 70 hamstring strains in the landing leg that cost pitchers time over this span, but just 56 to the push-off leg.

Strains of the push-off leg tend a bit more toward extremes, which (since this seems to be on the mild end of the spectrum) is good news for López.

I found that 46.2% of hurlers who strained their post leg’s hamstring came back within 20 days, whereas only 43.9% of those who strained the muscle in their landing legs returned that soon.

If the Twins’ initial read of this injury is accurate, the prognosis is good. López could well be back by the end of April. On average, though, the non-extreme versions of this injury still tend to keep pitchers on the shelf for 25 days, whichever leg is affected.

Alas, not all the news is good. One pattern that turned up in this analysis is the high rate of re-injury. If a pitcher suffers one hamstring injury, they have about a 25% chance of suffering a second one.

The 126 injuries I studied were suffered by 100 pitchers, and 21 of them suffered at least two strains.

Once you correct for the hurlers for whom the first strain coincided with or closely preceded the end of their career, it’s over a one-in-four shot that a guy who suffers one strain will suffer another.

The Twins themselves have dealt with this recently: Both Sonny Gray and Caleb Thielbar suffered multiple hamstring strains during their Twins tenures.

The Twins need their ace starter back as soon as possible, but they’ll have to be cautious in bringing him along, to minimize that risk of re-injury and ensure that he’s ramped back up when he returns.

Expect López to miss something in the neighborhood of three weeks.

In the meantime, the good news is that the team has good depth options at Triple-A St. Paul. Once López does assume his place in the rotation again, they could be stronger than ever for briefly having been without him.

Unfortunately, from now on, we’ll have to keep in mind that there’s a meaningful chance of this happening to him again.