3 sleepers among free-agent pitchers

It may feel like the World Series just ended a minute ago, but free agency has already officially begun. That means all the focus is on David Price, Jason Heyward, Zack Greinke, Yoenis Cespedes and the other stars who will command massive contracts. But what about the lesser-known or supposedly finished players who will get just a year or two? The opportunity for inexpensive value is there, so let's look at three pitchers who could far outshine their contracts.

Shawn Kelley, Padres
In seven seasons as a reliever in the Majors, Kelley has all of four saves. That's a great reminder that the save statistic is badly out of date and generally not worth looking at, but it also means that Kelley isn't the type to cash in during free agency. Keep that in mind when you compare Kelley's past three seasons to Trevor Rosenthal's 2013-15:

Kelley
30.8 K percentage
8.9 BB percentage
.224 average against
3.08 xFIP

Rosenthal
30.7 K percentage
9.6 BB percentage
.225 average against
3.07 xFIP

It's not a perfect comparison -- Rosenthal is younger, pitched 58 more innings and allowed fewer homers. But you get the point: A large part of the reason Kelley isn't thought of in near the same class is because he's been on teams with Mariano Rivera, David Robertson and Craig Kimbrel, meaning the ninth inning was never an option.

Kelley only throws two pitches. But his slider, which he threw more than all but two other pitchers in 2015, allows him to avoid a platoon split (for his career, lefties and righties have hit an even .233 against him). He threw it 436 times last year, and allowed just five extra-base hits. Assuming Kelley is healthy -- he missed time in September with a sore forearm, but was able to pitch five scoreless outings to finish out the year -- he's in line to be a low-cost upgrade for nearly any bullpen.

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Rich Hill, Red Sox
Hill's Major League debut came against the Florida Marlins in a game where Greg Maddux was pitching and Miguel Cabrera was playing left field, so, yes, he's been around for a while. He's pitched all of 104 1/3 innings in the past six seasons and has been a part of five organizations in that time, not including his time this summer with the independent Long Island Ducks. So why are we talking about a lefty who turns 36 in March?

Because in four late-season starts for the Red Sox -- his first Major League starts since July 2009 -- Hill wasn't just good, he was absurdly dominant. In 29 innings, he had a 36/5 K/BB and allowed only five runs, becoming the first pitcher since 1900 to make his season debut in September and put up double-digit strikeouts in three consecutive starts.

These are the smallest of small sample sizes, granted, and yet there's plenty of real, tangible evidence that Hill can be useful. His Statcast™ curveball spin rate of 2,705 rpm is the 11th-highest rate of the 111 pitchers who threw as many as he did, and the horizontal movement of 9.58 inches is the third highest behind Chris Bassitt and Aaron Nola. He also made a big change by moving from the first-base side of the rubber to the third-base side, going over 1.6 feet from 2014 to '15:

Hill is going to get a Major League deal this offseason, which would have been inconceivable even in August. Now, the question is whether someone gives him more than one year.

Trevor Cahill, Cubs
Once considered one of the brightest young starters in the game while with Oakland, Cahill was traded to Atlanta from Arizona on April 2 and lasted only two months there before being cut loose in June. He then spent most of the summer in the Minors for the Dodgers before opting out, eventually signing a Minor League deal with the Cubs in August and showing enough that he ended up on the playoff roster. Though he pitched only 11 games in relief for Chicago, he was a new man, tripling his strikeout rate from what it had been with the Braves -- from 11.0 percent to 34.3 percent -- and lowering his walk rate as well.

Like so many before him, Cahill picked up velocity after moving to the bullpen, adding over an extra mile per hour, but he also changed his mechanics and repertoire. Much was made in the spring of Cahill's attempts to throw more over the top while still with Arizona, but that was gone by the time he made it to Chicago. Gone, also, was the cutter that had been hit so hard with Atlanta, replaced by more sinkers and changeups -- the latter of which saw a strikeout rate that jumped from 14.8 percent with Atlanta to 32.5 percent with Chicago, in part because he threw it a career-high 26 percent of the time as a Cub.

Cahill's starting days may be over, but he still doesn't even turn 28 until March. He has had success in the past, and he had success late this year after reinventing himself.