If the shoe fits, play him.

Through April 19, Rangers outfielder Kevin Mench had no RBIs in 39 at-bats, significant foot pain and a shoe size of 12. Then he tried a 12 1â2 shoe. Since then, in seven games he has hit six home runs and driven in 20.

This story illustrates a bigger point. Sometimes shoes are too small. Occasionally players choose bats that are too heavy. Once in a while, pitchers’ release points veer slightly off.

But it’s much less typical for a good run-producing player at the height of his career to lose his ability permanently. Fantasy players who recognized this April 20 and picked up the Rangers slugger off the waiver wire are smiling right now.

Buy low, sell high is a tricky concept in fantasy baseball. It’s hard, when Milwaukee Brewers second baseman Rickie Weeks has no home runs through 20 games, to remember that you drafted him for his 20-homer, 20-steals potential. It’s hard to hold off when you’re offered Padres rookie Josh Barfield for him, since Barfield is off to a much better start. Weeks looks a bit lost out there.

Please don’t make this trade. Patience is mandatory. Teams that win fantasy baseball leagues do so by getting the best out of their players, not trading them before they hit their stride.

For that reason, our rising and falling sections will be replaced this week. This is the time to make the shrewd deals that will help you win your league. Trading the guys who have been carrying your team is risky, but if you get top value for them, you’ll be glad later.

Buy Low

Richie Sexson, 1B, Mariners

Strike now, while he still has just two dingers and an average barely over the Mendoza Line. Sexson is one of a handful of players with the ability to lead the American League in home runs, so write off his slow start and remember that getting him now probably means at least 30 more home runs this year, perhaps 40. Would I trade white-hot Jonny Gomes and his 10 homers for Sexson at two? You bet I would.

Jeff Kent, 2B, Dodgers

Is it possible that Kent is finally over the hill? Sure. He’s hitting .197 through 20 games with just three extra-base hits, so it’s conceivable that the 38-year-old is on the decline after many, many excellent years. I doubt it. Far more likely, Kent will rebound and post his 10th consecutive 20-homer, 90-RBI season. Offer a trade for him, and mention in passing something about creaky knees, or sciatica. See if that helps lower the price.

Sell high

Albert Pujols, 1B, Cardinals

Pujols is probably baseball’s finest hitter, and he’s off to his best start ever this year. Might he have a season for the ages? Yes. But teams also are beginning to walk him intentionally more because his protection in the Cards’ lineup is a bit dicey right now. In one of my leagues, I put Pujols on the trading block to see what he would command. Offers I received: Travis Hafner and Dontrelle Willis, Justin Morneau and Jose Contreras (that’s what the delete key is for), and Mark Teixeira and Curt Schilling. I took the last one, happily. Even if Pujols hits 50 home runs this year, four more than he ever has hit before, that’s really 38 more since he already has 12. Teixeira has just three this year, and is a great bet to hit 40, or 37 more. Add Schilling, and I’ll take that trade any day.

Jonny Gomes, OF, Devil Rays

To call Gomes clutch so far this season would be an understatement. The Devil Rays’ cleanup batter has been off the charts late in games. In close and late situations, defined by ESPN as situations in the seventh inning or later, with the team up one run, tied or with the potential tying run at least on deck, Gomes is hitting a cool 5-for-7 with three home runs and a major league-leading nine RBIs. He has hit 10 balls out of the park in 21 games so far. But how many home runs is Gomes really going to hit? He’s on pace for 80. Sell! Sell!

Quick hits

Which two pitchers among the league leaders in strikeouts are certain to fall off soon? How about Orlando Hernandez and Cory Lidle? Now in Arizona, El Duque leads the majors through April 26 with 35. His career best is 157 seven years ago, and he’s not exactly dominating opponents this year (5.27 ERA). Lidle’s offspeed pitches appear to be even slower this year, and he has opponents off balance for the Phillies. But don’t add him to your mixed-league roster expecting Ks; his career high is a paltry 126. Eli Marrero is one of six players through April 26 with at least four home runs and three stolen bases. This won’t last. He has been murdering inside pitches and totally unable to connect with anything on the outside half of the plate. Pitchers are beginning to catch on. Avoid him. I like Jeremy Bonderman as a two-start pitcher this coming week, against the Royals and Twins.