About one-third of the league is employing a six-man rotation, and even beyond that, teams are giving some of their top minor-league pitchers a start here and there.

In other words, it's a good time to be a hitter.

Matchups are more favorable across the board, so you might want to be more aggressive swapping out a trusted starter for a flavor-of-the week type. I'm not suggesting you sit your studs, but if you've gotten to where you automatically use a fringier Trey Mancini or Steven Souza type, it's worth exploring what else is out there for Week 25 (Sept. 18-25).

Here are my personal favorites owned in less than 80 percent of CBS Sports leagues:

Top 10 sleeper hitters for Week 25
Eddie Rosario Minnesota Twins LF
The Twins have the best matchups of any team this week, mostly because of their four games against the Tigers' ransacked rotation, and Eddie Rosario is heating up again, batting .478 (11 for 23) with three homers over his past six games. Of course, "heating up" is entirely relative. He's batting .322 with 18 homers and a .941 OPS over his past 80 games.
Matt Olson Oakland Athletics 1B
If that's not hot enough for you, Matt Olson has 10 home runs in his past 16 games, and though his overall strikeout rate is still discouraging, he has made huge strides in that area. The Athletics have the second-best matchups of any team this week, and even the three left-handers don't figure to be a problem seeing as Olson has an .827 OPS against lefties, having started against the past five.
Jose Martinez St. Louis Cardinals LF
My biggest hesitance with Jose Martinez is that the impending return of Jedd Gyorko (hamstring) could cut into his playing time, but he's probably safe for at least another week. He's batting .422 (19 for 45) with three homers and just six strikeouts in 12 games since becoming the regular first baseman and has pretty good matchups against the Reds and Pirates pitching staffs.
Carlos Gonzalez Colorado Rockies RF
Carlos Gonzalez has historically done his best work at home, as you'd expect for a Rockies hitter, so a week split between San Francisco and San Diego may not seem like the best thing for him. But the notoriously streaky hitter is showing his first real signs of life this season, batting .366 (15 for 41) with four homers and seven doubles in his last 13 games, and let's face it: The Giants and Padres have some terrible pitchers on staff.
Nicholas Castellanos Detroit Tigers 3B
Likewise, the splits aren't so much in Nicholas Castellanos' favor this week. He prefers lefties to righties, and the Tigers have only one on tap. But the righties include Jharel Cotton, Daniel Gossett, Daniel Mengden and Kyle Gibson, and Castellanos is batting .365 (46 for 126) with six homers in his past 31 games.
Kendrys Morales Toronto Blue Jays DH
The Blue Jays' matchups are nothing special this week, but they do include three lefties, against whom Kendrys Morales is batting .348 with a .970 OPS on the year. He has also hit six home runs in his last 19 games.
Dustin Pedroia Boston Red Sox 2B
Wait, Dustin Pedroia? A sleeper? Believe it or not, his ownership has fallen below the 80 percent threshold, thanks in part to injuries and a decline in home runs this year. He can still hit, though, and is proving it with a .433 (13 for 30) batting average in nine games back from the DL. He should pile up a few more multi-hit games against the Orioles and Reds pitching staffs this week.
Ozzie Albies Atlanta Braves 2B
Ozzie Albies is batting .346 (37 for 107) with a .965 OPS over his last 27 games, which is of course unsustainable, but his overall .292 and .839 marks may not be, judging by the peripherals. It gives him a point-per-game average close to Robinson Cano's, so unless you're selling out for home runs at this late stage of the season, he's a fine middle infield choice.
Jose Reyes New York Mets SS
Jose Reyes may seem like a reach compared to some of the other middle infield options available right now, but the fact is he had some ghastly luck earlier in the year, his batting average hovering around the Mendoza line despite his usual high contact rate. It's all evening out now, though, seeing as he's batting .366 (26 for 71) with four homers and eight steals over his last 20 games.
Jorge Polanco Minnesota Twins SS
Jorge Polanco's late-August home run binge is well behind him now, but he's still batting .289 (13 for 45) with two home runs in September. He has developed into a disciplined hitter who doesn't necessarily need big power to matter at a weak position, and he gets those same great matchups Eddie Rosario has.

Best hitter matchups for Week 25

1. Twins @NYY3, @DET4
2. Athletics @DET3, TEX3
3. Red Sox @BAL3, @CIN3
4. Indians @LAA3, @SEA3
5. Tigers OAK3, MIN4

Worst hitter matchups for Week 25

1. Giants COL2, @LAD3
2. Angels CLE3, @HOU3
3. Reds STL3, BOS3
4. Phillies LAD4, @ATL3
5. Padres ARI3, COL4