Matt Cain has a hamstring injury. USATSI

The Giants are perhaps baseball's hottest team, having won 13 of their last 14 games before Friday night's loss to the Rockies. The loss was compounded by starter Matt Cain having to leave early with a hamstring injury.

Now, Cain's been placed on the 15-day disabled list.

Needless to say, losing a member of its rotation is a big blow for any contender. For the Giants, they have an obvious elite top three in the rotation in Madison Bumgarner, Johnny Cueto and Jeff Samardzija. Cain, formerly known as an ace in his own right, was really starting to come around. In his last four starts, he had a 1.59 ERA and 17 strikeouts against only four walks (22 2/3 innings).

Now, after that big three, there's again a big drop-off to the back-end of the rotation with Jake Peavy (1-5, 7.26) badly struggling.

It appears that long reliever Albert Suarez will take Cain's rotation spot for the time being, though the Giants could use some off-days to just skip the fifth spot and use a four-man rotation temporarily.

Suarez, a 26-year-old rookie, has a 2.25 ERA in 12 innings this season. He worked five innings in relief of Cain on Friday, allowing his first runs (three of them) of the season. He made three Triple-A starts before getting called up, posting a 2.00 ERA in 18 innings.