Fantasy Baseball Waiver Wire Adds: Week 21

Super prospect Michael Kopech will make his debut this week, and he's certainly worth an add at pitcher. Who else should we target on the waiver wire?

The waiver wire has plenty of goodies available for the taking, so let's try to get a leg up on our fellow league members and make some moves where needed.

The four players below are all owned in fewer than 50% of ESPN leagues and could give your squad a shot in the arm as we enter the dog days of summer.

Harrison Bader - St. Louis Cardinals (OF)

ESPN Ownership: 38.9%

Following an injury to Dexter Fowler and a trade of Tommy Pham, playing time has opened up for the young Harrison Bader. So far, the speedy outfielder is making the most of his opportunities and deserves a look in fantasy outfields.

Over 289 plate appearances, Bader has nearly replicated his double-digit homer and steal seasons from the minors a year ago, as he now has 9 homers and 12 steals to his name. Bader has also inched close to the 50-run threshold (47), and that's thanks to a robust .351 on-base percentage (OBP).

Assuming he continues to receive consistent playing time, give him a look for some nice outfield depth.

Trevor Cahill - Oakland Athletics (SP)

ESPN Ownership: 38.4%

Since the All-Star break, the Oakland Athletics have lost eight baseball games. That's the exact recipe needed to catch the defending World Champion Houston Astros, and starting pitching like we are seeing from Trevor Cahill is a big part of it.

Over 86 2/3 innings, Cahill sports a sparkling 3.54 skill-interactive ERA (SIERA) thanks to a 24.9% strikeout rate and 26.0% fly-ball rate. He's also on track to post the lowest walk rate of his career, sitting at a 7.3% mark on August 20th.

The A's may not have flashy big name starters, but Cahill is certainly getting the job done and warrants some consideration in leagues where he's available.

Michael Kopech - Chicago White Sox (SP)

ESPN Ownership: 27.0%

One of the most ballyhooed prospects in baseball, Michael Kopech is set to make his debut for the Chicago White Sox on Tuesday, and there's plenty of reasons to be excited.

In 126 1/3 innings this year at Triple-A, the righty owns a ridiculous 31.3% strikeout rate, which is only his third-best mark at any stop in his career. It's also hard to ding Kopech for the long ball, as he's allowed only nine this season (0.64 home runs per nine innings pitched).

The youngster has struggled with his command a bit, as he's walked 11.1% of batters this season. But as long as he can harness that monster arsenal, he could provide a huge lift to fantasy staffs.

Todd Frazier - New York Mets (3B)

ESPN Ownership: 19.2%

Over the last two weeks, the New York Mets have been one of baseball's strongest offenses, and Todd Frazier has been a big part of that. Over this time frame, the corner infielder has ripped his way to a .417 weighted on-base average (wOBA), including a .208 isolated power (ISO) mark.

Frazier has started 12 contests during this recent span, and he's only gone hitless once. And that surging offensive attack is a big reason they've won their last four series as a club.

If your corner infield spots need a lift, check out Frazier.