A week of good or bad matchups can make all the difference in Fantasy baseball.

And before you make any kind of claim on the waiver wire or set any lineups for Week 13 (June 18-June 24), you need to see what Chris Towers has to say. As Senior Editor for Fantasy at CBS Sports, Towers is one of the most respected voices in the industry. If there's anybody who can spot an edge in a matchup or identify a player in position to break out, it's him.

In Week 12, Towers said the Marlins had some of the best matchups of the week and recommended playing J.T. Realmuto. The result? Realmuto recorded multiple hits in two of his first three games to begin the week, giving huge returns to anybody who followed Towers' advice.

Now, Towers has studied the upcoming schedule and is sharing his best and worst hitting matchups for Week 13 of Fantasy baseball. They'll help you figure out who to sit, start, add, and drop this week. 

One thing we can tell you for this week: Towers loves the matchups for Rockies second baseman D.J. LeMahieu.

"The Rockies have seven games at Coors Field in Week 13, and they get to take on the lowly Mets and Marlins," Towers said. "This is about as good a schedule a team can be facing, and you're going to want to take advantage by starting D.J. LeMahieu."

Towers has also identified a sleeper who gets a dream slate of pitching matchups this week. This hitter should return massive Fantasy numbers in multiple categories, and he might be on the waiver wire in your league right now.

So who should you start this week? Join SportsLine here to get CBS Sports Fantasy Editor Chris Towers' best and worst hitting matchups for Week 13, and see which sleeper you need to be all over because of his schedule.