Fantasy Baseball Waiver Wire: Tyler Glasnow, Austin Gomber claim rotation spots while Kole Calhoun keeps mashing

Kole Calhoun continues to put on a show while Tyler Glasnow and A.J. Minter settle into new roles. Scott White takes a look at the waiver wire.

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He didn't play Thursday — his team having the day off and all — but he did Wednesday and continued to do the thing he has done since returning from a two-week absence for an oblique injury in mid-June.

He homered.

It's something Kole Calhoun has done 13 times over the past six weeks to go along with a .302 batting average and 1.051 OPS. And while it would be easy to dismiss as a hot streak, the necessary correction for a player who's accustomed to a mid-.700s OPS but had only a .374 mark over the first two months, that line of thinking ignores some of the changes, both visible and invisible, behind the numbers.

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And it's why I'm saying Calhoun is still underowned at 62 percent.

First, the visible: Calhoun has dramatically altered his stance, settling into a crouch and holding his bat further away from his body in what's a little reminiscent of the changes Daniel Murphy made a couple years ago. And then, the invisible: His line-drive rate is up and fly-ball rate way up during that stretch, to levels never before seen in his career. Small adjustments can sometimes be completely transformative, as they were with Murphy.

After struggling with walks earlier in the season, A.J. Minter has found his composure at just the right time, with Arodys Vizcaino suffering a shoulder injury that sounds like it might keep him sidelined for the better part of the final two months. With the trade deadline past, the closer role is the rookie lefty's to run with,  and run with it he has so far, collecting his seventh save Thursday.

At 73 percent ownership, Pivetta barely makes the cut for a waiver wire column, but considering he has a 4.75 ERA, he may be hanging by a thread for some owners. His stuff has been awfully impressive of late, though, resulting in 28 strikeouts compared to just two walks over his past three starts. Granted, the first two of them had a less than favorable outcome, but BABIP has been his enemy, which explains how he has a FIP near 3.50.

As has been the issue throughout his professional career, Tyler Glasnow had trouble throwing strikes out of the Pirates bullpen before moving on to the Rays in the Chris Archer deal. The Rays weren't afraid to put the one-time uber prospect right into their rotation, though, and while he lasted only three innings Wednesday as he begins stretching out, he struck out five and walked one, throwing 70 percent of his pitches for strikes. He went especially heavy on his 99-mph four-seamer, a move that has worked wonders for another former Pirates enigma, Gerrit Cole, in his first year with a new team.

Batting fifth in the majors' best lineup after the Angels dealt him to the Red Sox, Ian Kinsler is in a prime RBI position and plated two runs on three hits Thursday. Even at 36, the guy rarely strikes out, and while he has already made up some ground over his past 45 games, his .239 BABIP entering play Thursday would suggest the arrow will keep point up.

There was some debate over which of Austin Gomber and Daniel Poncedeleon would claim Carlos Martinez's vacancy in the Cardinals rotation given that both took no-hitters deep into their spot starts earlier this month, but we've recently learned it'll be the former. Gomber doesn't have the most electric stuff, but he struck out 10.0 per nine innings during his time as a starter for Triple-A Memphis this year and has fared well out of the bullpen in the majors.