It's never too early to start thinking about making trades to improve your fantasy football team. And while overreacting to Week 1 results is usually not a wise decision, there were some developments in several NFL teams' openers that could be a harbinger of things to come the rest of the way.

So let's try to sort out what could turn out to be some early buying and selling opportunities for fantasy managers.

OPENING STATEMENTS: 32 things we learned from NFL's Week 1 games

These players saw their fantasy values increase or decrease most based on their performances in Week 1:

Fantasy football buy candidates

RB J.K. Dobbins, Los Angeles Chargers: After suffering devastating season-ending injuries in consecutive campaigns in Baltimore, Dobbins has a new home in Los Angeles. He looked healthy and strong, rolling up 135 yards and a touchdown on 10 carries. Coach Jim Harbaugh and offensive coordinator Greg Roman love to run the ball, and if Dobbins can stay healthy, his fantasy rise could rapidly continue.

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TE Isaiah Likely, Baltimore Ravens: While plenty of fantasy managers drafted Mark Andrews as a must-start tight end, Likely showed there's more than enough room for two tight ends in Charm City. He blew up for nine receptions, 111 yards and one score, and he came within a big toe of a second touchdown.

WR Jameson Williams, Detroit Lions: Williams took center stage Sunday night against the Los Angeles Rams, going for five receptions, 121 yards and a touchdown. While he will still have to contend with WR Amon-Ra St. Brown and TE Sam LaPorta for targets, he has rapidly moved from WR4 status to WR2.

WR Alec Pierce, Indianapolis Colts: Pierce is going to be a hot property off the waiver wire in Week 2 after registering three receptions for 125 yards and a touchdown, and jelling nicely with QB Anthony Richardson. He went from fantasy afterthought to a fantasy waiver-wire darling in a hot minute.

QB Baker Mayfield, Tampa Bay Buccaneers: Mayfield started the season on fire against the Washington Commanders, throwing for 289 yards with four touchdowns and no interceptions, while also rushing for 21 yards. He was the only quarterback in the NFL to throw for four scores. He’ll face a tougher matchup in Week 2 at Detroit, but should at least be back in the high-end QB2 conversation.

Fantasy football sell candidates

QB Kirk Cousins, Atlanta Falcons: Cousins looked uncomfortable for most of his Falcons debut, and he was a little rusty after returning from a major injury. Expectations are sky-high in Atlanta, and he laid a major egg in his first test, falling out of QB1 territory for now.

QB Deshaun Watson, Cleveland Browns: Watson has had a rocky road since signing a lucrative contract before the 2022 season, including a nagging shoulder injury that kept him out most of last year. In this make-or-break season, he was a disaster in Week 1 (24-for-45, 169 yards). Granted, his offensive line is dinged up already, but he looked lost yet again.

RB Travis Etienne, Jacksonville Jaguars: Etienne was expected to be the bellcow for the Jaguars, but a devastating fumble thrust backup Tank Bigsby into action, and he racked up 73 yards on 12 carries (6.1 ypc). Conversely, Etienne averaged less than four yards per tote. It’s a backfield situation worth following closely.

RB Raheem Mostert, Miami Dolphins: Mostert led the NFL with 18 rushing touchdowns, and he was tied for the league lead with 21 total scores. That was 2023, this is 2024, and he debuted with just six rushes for nine yards, while adding two receptions for 10 yards. Not only did RB De’Von Achane outproduce him, but journeyman RB Jeff Wilson Jr. did, too.

TE Dalton Schultz, Houston Texans: The offseason acquisitions of WR Stefon Diggs and RB Joe Mixon upgraded what was already an excellent Texans passing attack. Schultz appears to be hurt most by the new additions, making him a TE2 at best.