As the weekend approaches, there's a lot of value sitting on fantasy waiver wires that can help managers in the short term or potentially stick around for much longer. Below, I'll break down six players widely available in Yahoo Fantasy Baseball leagues whom I'm targeting ahead of Week 17.

Tristan Casas, 1B, Boston Red Sox, 52% rostered

Breaking the 50% rule a bit here, but that's OK; Casas has earned it. He has been on a heater lately, ranking as the 59th-best player in fantasy baseball over the past month.

He's batting .353 in that span, ripping off six dingers in the past two weeks, with 11 RBI and 15 runs scored.

Just an absolute tear.

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Per Fangraphs, Casas has nearly doubled his barrel rate compared to last season (up to 14.6%) and increased his exit velocity to 91.7 and hard-hit rate to 46.7%. He also has the 10th-best wRC+ among all 1B, at 126. He's starting to look like a poor man's Matt Olsen, so he should not be on waivers.

Wilmer Flores, 1B, 2B, 3B, San Francisco Giants, 41%

He's tearing the leather off the ball, slugging .895 over the past two weeks, with a .432 on-base percentage and 1.327 OPS. His multipositional eligibility is incredible for fantasy, and he has been spending most of his time between DH, first and third base.

The knock on Flores is that he's still in a platoon, despite posting a solid .263 BA and slugging .517 against right-handed pitching. It's becoming increasingly challenging to bench him, however, as he's one of the hottest hitters in baseball. He should be rostered in more than 50% of leagues.

Sal Frelick, OF, Milwaukee Brewers, 39%

Frelick made his MLB debut just six days ago and is already impacting the Brew Crew. He scored a run in his first five games as a pro and is batting a ridiculous .417/.556/.667 with a 1.222 OPS to begin his career. He has one home run in that span and has shown exceptional plate discipline, drawing five walks in as many games. He's going to regress, but he has consistently batted between the fourth and sixth spots in the lineup, so there's both potential and upside for Frelick to have staying power in 12-team leagues for the next week. We have yet to see his speed on display, but he stole eight bases in Triple-A before being called up.

Adam Ottavino, RP, New York Mets 26%

In a stunning after-hours trade, former Mets closer David Robertson was dealt to the Miami Marlins for a couple of minor leaguers Thursday. Ottavino should take over as the primary closer, as he has tallied six saves with 11 holds for the Mets this season. Brooks Raley might eat into some late-inning work, but Ottavino has more experience and is the preferred target if you're looking for saves.

Don't expect much from him in the K's department, though, as his K/9 rate is his lowest since 2013. The Mets are beyond underwhelming, but with so few closers available on waivers, Ottavino should be rostered in most leagues.

Kevin Ginkel, RP, Arizona Diamondbacks, 27%

The D-Backs are in the thick of a tight race in the NL West and are a half-game out of an NL wild-card spot. The Arizona bullpen has been disappointing for much of the season, as one of 11 teams with a save percentage below 59%. Enter Ginkel, whose 2.31 ERA through 39 innings is the lowest of any reliever for the D-Backs who has registered at least three saves this year.

Ginkel's K percentage is the lowest of the group at 22%, but he has been stellar since entering high-leverage situations. Since becoming the closer July 18, he has recorded three saves with a 1.80 ERA and 1.00 WHIP across five innings. He's ranked 120th over the past month in H2H formats, and that could climb even higher with continued success as the closer.

Johnny Cueto, SP, Miami Marlins, 8%

If you're looking for a streamer this weekend, look no further than Cueto. Since coming off the injured list on July 10, he has given up one run across nine innings, along with an effective 9 Ks and 0.56 WHIP. Luckily for him, he'll face the Detroit Tigers, who rank in the bottom 10 in batting against RHP this season.

And it's even worse on the road for Detroit, as the Tigers rank dead last in MLB with a .211 BA against righties. Cueto is worthy of a spot start Saturday and could hold onto the fifth spot in the rotation (assuming Eury Pérez stays in the minors).