Cardinals receiver Marvin Harrison Jr. leads all rookies this season with seven touchdown catches, and yet there's still a sense that his first NFL season has been underwhelming. 

Drafted fourth overall out of Ohio State and the son of a Pro Football Hall of Famer, Harrison went to Arizona with high expectations, but has yet to find a consistent connection with quarterback Kyler Murray.

Three weeks ago, the Cardinals were 6-4 and surprise leaders atop the NFC West standings, but they've dropped three straight, with interceptions on passes intended for Harrison in each of their past two losses.

Harrison flashed big-play potential in Week 2 when he caught touchdowns of 60 and 23 yards in the first eight minutes of a 41-10 rout of the Rams, part of a four-catch, 130-yard day. But he has topped 100 yards only once since then — he had eight 100-yard games with the Buckeyes last season — and doesn't have a single catch of longer than 25 yards in the past 11 games.

Harrison's catch rate — the percentage of targeted throws that result in receptions — is just 52%, which ranks 23rd out of 27 rookies with 20-plus targets this season. He's caught more than half the passes thrown his way just three times in 13 games, so out of 96 NFL players with 50-plus targets, his catch rate ranks 91st.

This can speak to the attention opposing defenses are already giving him. Arizona's leading receiver has actually been tight end Trey McBride, who's on pace for more than 100 catches and 1,000 receiving yards. It's reasonable to think that Harrison will be closer to those numbers in his second season, while continuing to be the team's best touchdown threat in the passing game.

Flags flying for Lions rookie corner

Detroit has matched Kansas City for the best record in the NFL, and its defense, tied for second in points allowed, is a big part of that. But the Lions have done that while first-round pick Terrion Arnold has struggled while playing the second-most defensive snaps on the team.

Arnold has had a particular problem with penalties -- he's been flagged 11 times for an NFL-high 167 yards, putting him on pace to be the first player at any position with 200 penalty yards since the Saints' Brandon Browner had 209 in 2015. Arnold doesn't have any interceptions as a rookie, and his overall coverage has been poor enough that Pro Football Focus ranks him 108th out of 118 NFL cornerbacks.

As the Lions try to hold on to the NFC's top seed and home-field advantage up until the Super Bowl, they face a difficult final month that includes top-10 offenses in the Bills, 49ers and Vikings. That will put more of a spotlight on Arnold going into the playoffs, but Lions coach Dan Campbell offered support for him this week, saying he's seen progress at a time when many rookies tire and drop off.

"That's where Arnold's at. He's starting to push through this," Campbell said. "He's gaining enough valuable reps and experience. He's not letting the grind of the season wear him down, and he's getting better."

In drafting Arnold and trading for corner Carlton Davis, Detroit actively worked to upgrade its defensive secondary in the offseason. The team's defense has improved from 19th to 10th in total defense, and from 30th to 10th in yards per pass allowed.

Pearsall forgotten by 49ers

Five weeks ago, 49ers first-round pick Ricky Pearsall had a 46-yard touchdown and 73 receiving yards in a win against the Bucs, but in four games since, he's nearly disappeared in San Francisco's passing game. Pearsall has played in 61% of the offensive snaps as a No. 3 receiver behind Deebo Samuel and Jauan Jennings, but in those four games, he has just five total targets, with only one catch for 5 yards. 

San Francisco ended a three-game losing streak with a rout of the Bears on Sunday, but the 49ers are on the outside looking in at the NFC playoff picture. It would take a strong finish — against the Rams, Dolphins, Lions and Cardinals no less — for them to have a shot at the postseason.

Rookie sacks hard to find

We've known since the draft that there wasn't a strong class of defensive talent, but with four weeks left in the regular season, only 12 rookies have more than one sack, and the leader is the Rams' Braden Fiske, who has six. That puts him on pace for the lowest total to lead all rookies since Chase Young had 7.5 in 2020.

Among those with disappointing totals is Minnesota edge rusher Dallas Turner, who went 17th overall out of Alabama and has only one sack, with no sacks or tackles for loss since Week 1. The Vikings have a great defensive front and rank fourth in the NFL in total sacks, so it's more a function of Turner not being able to get on the field. He hasn't played more than 26 snaps in a game since the season opener. If the Vikings let free-agent-to-be Pat Jones II sign elsewhere — he has seven sacks in a breakout season — that would free up more work for Turner next year.

Rookie QBs close to 3,000 passing yards

We've written a lot about this year's rookie quarterbacks, and the top three are close enough in passing yards to each other that all of them — Washington's Jayden Daniels, Denver's Bo Nix and Chicago's Caleb Williams — could pass 3,000 for the season this weekend. Nix needs 158 yards, Daniels needs 181 and Williams 254, and whenever they get there, it will mark just the third time in NFL history that three rookies pass for 3,000-plus yards in the same season. 

The previous two times are a reminder of how hit-and-miss NFL careers can be even after a prolific rookie season. In 2019, three quarterbacks threw for 3,000 in Kyler Murray, Daniel Jones and Gardner Minshew, and in 2012, there were five, running the gamut from multiple Pro Bowl selections Andrew Luck and Russell Wilson to Ryan Tannehill, Robert Griffin III and Brandon Weeden.

Greg Auman is an NFL Reporter for FOX Sports. He previously spent a decade covering the Buccaneers for the Tampa Bay Times and The Athletic. You can follow him on Twitter at @gregauman.

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