Fantasy Baseball Waiver Wire: Week of September 7

We are down to the final stretch of the fantasy baseball season, and your playoffs are underway. Now is the time to refine your strategy, hunt matchups, and lean into streaming pitchers. From here on out, every single day matters, and your roster will be constantly changing.

As your roster continues to change and short-term gains become the focus, you need to be ready to add and drop by the day. Today, we have five players who should help you get through this week. Or, at least through a pitcher’s next start. Because more movement will be on the pitching side, we leaned a little more heavily into arms this week.

Stats as of the morning of September 7. Ownership percentages via ESPN.

Mickey Gasper – C – Boston Red Sox (15.2%)

2026 Stats: .276/.387/.500, 8 HR, 148 wRC+

The catcher position can be a difficult one to fill in fantasy, especially this late in the season. Riding the hot hand is more important than predicting what a player will do over a month (or longer span), and there are few hitters who are hotter than Gasper.

Over the past month, Gasper has slashed .347/.529/.918 with eight home runs in 68 plate appearances. A bizarre hot streak that might not last, but I would want to find out if it will or won’t while he is on my team. Boston is going up against the Angels and their weak pitching, which only helps Gasper’s value.

Kody Clemens – UTL – Minnesota Twins (32.8%)

2026 Stats: .238/.298/.464, 24 HR, 110 wRC+

I never expected Kody Clemens to develop into who he is today. A useful utility player is now more of an everyday player who just happens to move around while providing a power boost to the Twins lineup. He’s been great throughout the season but has been on fire as of late.

A player who can slot into multiple positions is something I would always suggest having down the stretch. A bad matchup or day off for one of your regular starters can be filled with a player who has done enough to be rosterable in most leagues. A luxury you need to have come playoff time.

Andrew Painter – SP – Philadelphia Phillies (17.9%)

2026 Stats: 105.1 IP, 5.55 ERA, 4.66 FIP, 7.78 K/9, 3.16 BB/9

Listen, I know Painter has not been quite what we all hoped he would be this season. Luckily, you only need him to provide one start for you, which will come against the Astros, a lineup I think he could navigate rather well.

Painter has allowed three or fewer runs in six of his past seven starts, five of which included six or more strikeouts. He’s coming off a seven-inning, two-hit, no-run game and looking like the pitcher we all expected to see this season.

Jake Bennett – SP – Boston Red Sox (33.6%)

2026 Stats: 99.2 IP, 3.34 ERA, 3.28 FIP, 7.31 K/9, 1.63 BB/9

Jake Bennett has put together a nice rookie season in Boston, but it has seen a couple of shaky starts in the past month. While we cannot erase those, if you look around those back-to-back four-run starts, you’ll see quality start after quality start.

This week’s matchup will be against an Angels lineup that no pitcher should fear. We know Bennett often works into the sixth or seventh inning and has the ability to strike out six or seven batters. I love the matchup and the upside it brings, but I also love the high floor. I don’t think you can miss with this addition.

Mason Montgomery – RP – Pittsburgh Pirates (17.2%)

2026 Stats: 59.2 IP, 10 SV, 2.87 ERA, 2.31 FIP, 13.88 K/9, 3.47 BB/9

Let’s make this very simple. The last time Mason Montgomery allowed an earned run was July 26. Before that, you’ll have to go back to June 26. Thankfully, you won’t have to worry about him pitching on September 26. He’s started to get save opportunities, he racks up strikeouts, and he only has two walks since August 1.

I think Montgomery is not just on a hot streak, but quickly developing into one of the more underrated closers in the game. He has to prove it over a longer period of time, but all signs are pointing in the right direction.