MADISON, Wis. (AP) — Joe Ferguson is making a name for himself at No. 6 Wisconsin.

It has nothing to do with being athletic director Barry Alvarez's grandson.

The senior safety has turned into a key contributor on the Badgers' tough defense, the latest in a recent line of reserves who have been productive when stepping up because of injuries or when coach Paul Chryst dips into roster depth.

Somehow, some way, Ferguson always seems to be around the ball of late.

Ferguson had two interceptions, a fumble recovery and two pass deflections in the 45-17 win last week over Indiana. He had an interception two weeks ago in the victory over Illinois .

"You see the athletic ability. He's got a nose for the ball," defensive coordinator Jim Leonhard said Wednesday.

Ferguson recovered a fumble three weeks ago against Maryland. In the season opener against Utah State, Ferguson returned an interception 99 yards for a touchdown.

Ferguson has seen his playing time increase of late because of a right leg injury to starter D'Cota Dixon, the leader in the secondary for Wisconsin (9-0, 6-0 Big Ten, No. 8 CFP).

As it turns out, there hasn't been much of a drop-off.

"A lot of it is your talent. On the hand, it's your mindset going into the game. You've got to be thinking ball, you've got to be thinking interception, you've got to be thinking 'strip the ball,'" Ferguson said.

He sounds a lot like Leonhard, who also played at Wisconsin. Leonhard was a former walk-on who emerged to become a ball-hawking safety in college and the NFL.

"I've been saying it for a while — you just listen to what coach Leonhard says, good things happen," Ferguson said.

Depth has helped Wisconsin withstand key injuries. Besides Dixon, the Badgers lost perhaps their most dynamic defender, inside linebacker Jack Cichy, to a season-ending knee injury in preseason camp.

That position also happens to be one of the deepest on the team, so Chris Orr stepped in to replace Cichy alongside T.J. Edwards. Ryan Connelly is the third member of the inside linebacker rotation.

Now Connelly is stepping into replace Orr this weekend against No. 25 Iowa, with Orr out with left leg injury. A year ago, Connelly stepped into replace Cichy when Cichy was lost for the season with a torn pectoral muscle. Wisconsin's defense continued to play well then, too.

Other backups have also played well in limited opportunities. Outside linebacker Tyler Johnson has two forced fumbles and a sack over the last two weeks. On offense, Chryst has turned to freshman running back Garrett Groshek in key, second-half situations.

In most instances, reserves get spurts of playing time early in the season, inserted into different situations. When an injury hits, or if starters need a breather for a drive or two in a key game later in the season, a reserve steps up. If they make big plays during those few series, they earn more playing time.

It's what happened to outside linebacker Garret Dooley, who filled in capably last season when then-starters T.J. Watt and Vince Biegel were hurt. Dooley is now one of the rocks on this year's defense with a team-high 6 1/2 sacks.

"Whether in practice or whatever, (coaches) do a good job of rotating guys," Dooley said. "When I had that start due to injury, I've kind of been in that spot (to play in key games.) It wasn't as nerve-wracking."

Ferguson has been bothered by injuries over his career. But this season is different. Coaches say they noticed a difference in physicality in kickoff coverage earlier in the year.

It has carried over to defense as he's picked up more opportunities to play.

"He's a guy who as a senior is playing his best football," Chryst said, "and has fun playing and that can be contagious."

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