Fantasy Football championships are not necessarily won or lost on draft day. The best owners know how to manage their rosters during the season, building on their strengths and repairing their weaknesses from week to week. Yahoo Fantasy Football expert Brandon Funston shares three strategies that can help you do exactly that this season.

1. Own the Waiver Wire

Rule number one, according to Funston: always watch the waiver wire. He says, “You’re always trying to swap out [weaker] parts on your team for better parts.”

But how do you know whether that no-name tight end who caught three touchdown passes last Sunday will ever see the end zone again? Funston recommends asking three questions about a player before you decide to pick him up: “Whom will he be playing against in the next few weeks?” “Realistically, what is his role?” And “What is his situation?”

A weak upcoming schedule provides favorable matchups and raises a player’s value. If he’s earned a larger role on his team, he may be worth picking up. If he’s a backup subbing for a star who’s expected to return soon, you might want to pass.

2. Claim Now, Trade Later

If you spot a rising star on the waiver wire, go ahead and claim him, even if you don’t need him immediately. If you have an open roster spot, it’s smart to pick up a productive player just to keep him off opposing teams. Who knows? Maybe he’ll be hot when one of your starters gets injured. And you can always trade him for a player who fills a need for you later in the season.

3. Ditch the ‘D’

Loyalty is a virtue in real life, but not in fantasy football. Funston recommends adding and dropping team defenses throughout the season based on weekly matchups. He says, “Defense is so random week in and week out that it doesn’t make sense to keep just one.” Instead, Funston looks for defenses that either have home field advantage or are playing against a suspect quarterback or a weak offense. “You can usually find one that meets those variables each week,” he adds. “It’s way better than sticking with one team, especially if it has to face Peyton Manning this Sunday.”

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