If the 2008 NFL season has proved anything to fantasy football players it’s that there are no sure things every week.

The top three quarterbacks this year (according to standard scoring formats) have been Denver’s Jay Cutler, Dallas’ Tony Romo and Arizona’s Kurt Warner.

Although Cutler has been a big producer this year, he’s thrown just two touchdowns in his last two games after throwing eight in his first three.

Romo has similar stats, having performed extremely well in three games and just OK in two others.

Warner has probably been the most consistent big-time producer of the top three. After struggling in his opening game, he’s gone four straight weeks with huge numbers.

The trends are the same among running backs, as well. The top producer — Atlanta’s Michael Turner —has had three very good weeks but was virtually invisible in two others. Frank Gore has been more consistent, showing up every game and posting huge numbers in the season-opener and Week 3.

Dallas’ Marion Barber was a monster the first three weeks of the season, but has done little the last two Sundays. And don’t even discuss the issue with LaDainian Tomlinson owners who have not even come close to getting the production they expected from the overall No. 1 pick.

A glance at the top three wide receivers shows more of the same. Green Bay’s Greg Jennings has been up and down, scoring big points in Weeks 2, 3 and 5 and just a few points in Weeks 1 and 3.

Arizona’s Anquan Boldin is listed as the No. 3 receiver but his numbers are skewed by a huge performance in Week 2. He missed Sunday’s game because of injury and had two other weeks this year where he did little.

These numbers prove the adage that just because you have the best player at a position, it doesn’t guarantee he’s going to produce every week. You still need to try to improve your full roster every week, from quarterback on down to kicker and defense.

Some of the most popular guys on the waiver this week figure to be Chicago quarterback Kyle Orton, Arizona running back Tim Hightower, and perhaps N.Y. Jets wideout Chansi Stuckey (who may have been dropped before his team’s bye week).

All three are solid pick-ups. Orton won’t have the luxury of throwing against the Lions’ defense every week, but Sunday was his third productive game in a row and there are no stellar pass defenses in the NFC North.

Hightower has yet to have a good yardage game but he’s been finding the end zone at least once every week. Stuckey started strong and then faded a little, but with Brett Favre getting more and more comfortable in the Jets’ passing scheme, Stuckey should get his share of opportunities.

Another player who may get picked up this week but is a real long shot is N.Y. Giants receiver Sinorice Moss. He had his first career two-touchdown game Sunday but, with Plaxico Burress returning to the lineup, he’ll drop back to No. 4 or 5 on the depth chart.

Some other players to consider off the wire are Miami quarterback Chad Pennington (he’s broken the 200-yard passing barrier the past two weeks), Buffalo running back Fret Jackson (who has performed well both as a runner and receiver when spelling Marshawn Lynch), and Arizona’s Steve Breaston (who will be No. 2 in a high-powered offense as long as Anquan Boldin is out).