Up to now, most of your fantasy football season has been about putting together the best team you can: Scoring the most points each week and not worrying too much about moves your head-to-head opponents may be making beyond rooting against their players on Sundays.
Now, with Week 13 likely to determine playoff brackets and single-elimination games the rest of the way in most leagues, it's time to get away from the bowling or golf mentality.
It's not just about a solo high score built factoring in byes, injuries and your team's situations. You've got to consider opponents and counter their moves.
Most likely, they'll be doing the same to you.
John Hansen, an analyst for DirecTV's Fantasy Zone channel who has worked in fantasy sports for about two decades, says fantasy players are smarter than ever, creating big parity in leagues and less of an edge for savvy players to win.
''It's never been more popular and competitive than ever - particularly this year,'' said Hansen, who also hosts a fantasy radio show on SiriusXM. ''I'm now to the point where I just want to be wrong fewer times than the other guy because we're all going to be wrong.''
It's a competitiveness Hansen sees play out on Sundays with people looking to Fantasy Zone - a Red Zone-like channel that skips around games to talk only about fantasy football - for immediate analysis. They're even asking who to start the following week on Twitter right after the games end, Hansen said.
All's fair, he says, when you're trying to win a league - as long as it's within the rule structure.
''Anything you can do to gain an advantage,'' he said.
Here are some things when doing opposition research that fall into that spirit of gamesmanship:
BLOCKAGE: NO EASY BUCKETS
Take a moment and look at your opponent's team. What would you do in his or her shoes?
Think about who will be starting and where the owner will likely be scrambling. In a solid league, it's unlikely that your opponent will have a team with zero holes.
Compare that to the free agent list and you can probably find players you can pick up who might sit on your bench, but give you value by not tallying points for the other team.
Owners of players like tight end Jordan Reed, quarterback Robert Griffin III or any of several running backs or wide receivers facing injury questions are in this spot right now. It could also work with a second defense if your opponent's defense has a bad matchup, like the Eagles at Dallas.
SWING FOR THE FENCES
In most leagues, getting a win is the biggest key. So how good are your chances if your opponent starts the best possible lineup?
Answering that could make the difference with whether you try to play conservatively or deliver a knockout blow, Hansen says.
''If they're stacked and loaded ... I really need to shoot for the stars here,'' he said. ''A fairly boring play might not be good for your team.''
Murray, after all, is more likely than Jackson to put up a goose egg or a really lousy score (while exciting, he's far more unproven).
With playoffs on the line, you'll also want to know your league's settings for tiebreakers and look not only at your head-to-head opponent, but anyone near you in the standings who you're jockeying for position against.
DEPTH FOR STARTERS
The bye weeks are over, so in some ways, you're back to Week 1 and able to start your best players.
But in leagues with late trading deadlines, you might be able to take advantage of the craziness of the NFL so far. In fantasy, the varied performances have led to active free agency and waiver periods each week.
''I'd be willing to trade depth for the best possible starting lineup,'' Hansen said.
Hansen said that late-season strategy sprouts from an early-season approach of trying to spread the talent around the roster, drafting one high-end stud at each position.
That way, you have fewer places where you need one up-and-coming player to ascend to be a start-worthy player.
Picking backups to high-value fantasy assets is not new - it's standard operating procedure in many leagues. But players more often think about backing up their own guys rather than handcuffing against an opponent's player.
Nothing like declaring ''Game on'' to an opponent like hearing about him or her go to the waiver wire to pick up a backup, then seeing that player already sitting on your bench.
Oskar Garcia can be reached on Twitter at http://twitter.com/oskargarcia