Fantasy owners have a variety of reasons for deciding which players to drop and which ones to pick up, but sometimes the decisions are made for them. Such is the case this week. As soon as Tom Brady finished limping off the field, fantasy owners everywhere familiarized themselves with his backup, Matt Cassel, who will now guide the team through the 2008 season.

The 6-foot-4 USC product has very little starting experience (in college he watched Carson Palmer and Matt Leinart from the sidelines) but he performed well in Sunday's 17-10 win over Kansas City -- 13 of 18 for 152 yards. Cassel has inherited a lineup containing prime fantasy weapons Randy Moss and Wes Welker. That means Cassel, himself, is now a prime fantasy prospect.

Oh, how quickly things can change in the rough and tumble world of football ...

Waiver wires work differently from league to league, so the only advice to give with regard to acquiring Cassel is -- if eligible, move quicker than Carl Lewis on his best day.

However, for those who miss out on the Cassel sweepstakes, consider these other waiver wire candidates ...

Yes, Brandon Marshall will return for Week 2, but Royal's accomplishments against Oakland on Monday night had little to do with Marshall's absence. The rookie from Virginia Tech caught nine balls, one for a 26-yard score, and his 146 yards lead the NFL after one week of action. Royal was magnificent against a pair of very good Raiders cornerbacks on a night when other Bronco targets had trouble (no other receiver caught more than two passes). When Marshall returns he'll take back his "go-to-guy" status, but Royal has undoubtedly earned a bigger stake in the offensive gameplan moving forward.

Jackson ripped apart St. Louis for six catches and 106 yards. Of course, it's fair to mention that Jackson's teammates -- Hank Baskett and Greg Lewis -- also eclipsed the 100-yard mark against the lowly Rams secondary. But fantasy owners know Lewis is limited, and almost all of Baskett's yards on Sunday came on one play. In terms of fantasy potential, Jackson is still an unknown. And Donovan McNabb looked to his rookie receiver more than any of his other targets; McNabb unsuccessfully threw deep to Jackson twice in the first half, and threw at him on three consecutive downs on the Eagles' final drive of the half. Jackson could be the speed receiver McNabb (and fantasy owners) has been waiting for.

The arrival of Alge Crumpler in Tennessee prompted most fantasy owners to prefer him over Scaife in drafts this summer. But Vince Young has always favored his former Longhorn teammate, which explains why Scaife caught six passes for 105 yards on Sunday, and Crumpler caught just one ball for minimal yardage. What's more, Scaife has more big-play ability than his counterpart, evidenced by the 27-yard pass he caught from Young and the 44-yard play he made later with Kerry Collins in the game. Young's injury could change matters in the next week or two, but long-term, Scaife just might be the better tight end option in Tennessee.

Looking for someone to strengthen your kicking game? Consider Prater, who made both of his attempts on Monday night -- one from 43 yards. Jason Elam had a long track record of success kicking in Denver, and now Prater will be given the same high altitude advantages. The Broncos are a team being picked to challenge in the AFC West, and their high-flying passing game should provide Prater with plenty of opportunities. For fantasy owners serious about improving their kicking game, Prater's Week 1 performance stands out from the other likely free agent fantasy options.

Here is a look at this week's buy and sell candidates:

Derek Anderson, QB, Browns

The Cowboys made Anderson and his Cleveland teammates look like a bunch of clowns in Week 1, but Dallas and its vaunted defense will probably do that to a number of opposing offenses this year. Anderson still has the best 1-2 punch in the game (Kellen Winslow and Braylon Edwards) and the Browns passing game will regroup. There is no better time for fantasy owners to make a move on a player like Anderson than in the wake of a disappointing performance against a superb opponent.

Rashard Mendenhall, RB Steelers

Mendenhall's professional debut was a disaster -- 28 yards on 10 carries, no catches, no touchdowns. Quite the opposite, teammate Willie Parker had a huge afternoon (138 yards, three scores). But Mendenhall is too talented to disappear from the Pittsburgh gameplan, and will improve as the season progresses. Fantasy owners should be able to pick him up for a bargain rate right now. He's high risk, but he could offer a good return on the investment later in the year.

Pierre Thomas, RB Saints

A fellow University of Illinois grad, Thomas looked sharp for New Orleans on Sunday. He averaged 5.2 yards per carry -- a yard and a half better than Reggie Bush's average -- and should see an increased workload in the coming weeks. New Orleans must know that Bush is far too valuable as a receiver to waste as a 20-carry back (something he has never been in college or the NFL). Fantasy owners can still likely acquire Thomas for a modest investment.

Tom Brady, QB, Patriots

Sorry, bad joke.

Lendale White, RB, Titans

Against Jacksonville, White and Chris Johnson were given an equal number of carries to work with. White averaged 2.7 yards per carry; Johnson averaged 6.2. Sure, White did score the Titans' lone rushing score, but it won't be long before the workload tilts in Johnson's favor. Jeff Fisher will most likely continue to use White as a complement to his speedy rookie, but there is now no question as to who the playmaker is in the Tennessee backfield.

DeAngelo Williams, RB, Panthers

John Fox will want to use both of his backs this year, so Carolina's situation is one for fantasy owners to be concerned with, anyhow. But Williams is an even bigger concern than rookie teammate Jonathan Stewart. On Sunday, Stewart posted a better average per carry and had a longer run -- and the thing is, Stewart might not even be at full health yet. Williams' 86-yard performance will help fantasy owners unload him for something of value. If you drafted Williams, there is no better time to bail out than the present.

Matt Forte, RB, Bears

Forte's statline from this week was impressive -- 23 carries for 123 yards and a touchdown. But take away his 50-yard score against Indianapolis and see what you have -- 22 carries for 73 yards (3.3 average per carry). With a back like Barry Sanders or Gale Sayers it's unfair to do such a thing, because their yards are designed to come on big plays. But Forte? He's a three-yards-and-a-cloud-of-dust type. Look, Forte could be in for a fine season, but he's not going to sweep the league off its feet like Adrian Peterson did last year. If the trading is good, consider unloading him for a handsome reward.

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