As the Vikings kickoff training camp this week at TCO Performance Center in Eagan, everyone is looking at the defense to see how the depth chart will change with a lot of new faces on that side of the ball.

Not only is the club dealing with the loss of veteran starters like Xavier Rhodes, Trae Waynes and Mackenzie Alexander in the secondary, the defensive line has lost Everson Griffen, Linval Joseph and now Michael Pierce, their highly touted free-agent nose tackle who opted out of the season due to medical concerns over the coronavirus.

But listening to Vikings brass you wouldn't think they have any cause for worry.

There's a lot of confidence coming from the coaching staff and the front office that this team has some young players who are ready to make a big leap.

One of those players is Jaleel Johnson, the 2017 fourth-round pick who played a career-high 408 snaps at defensive tackle last season while starting three games.

Johnson posted 3½ sacks, which ranked fourth on the team behind Danielle Hunter (14½), Griffen (eight), and Ifeadi Odenigbo (seven). He added five tackles for loss, which was tied with Stephen Weatherly and Harrison Smith for the seventh-best mark and had five QB hits.

Johnson told me last season that he could tell he was improving as he got more and more playing time.

"A lot, just techniques and just being a better student of the game and just overall playing well," he said. "It has been a lot better."

Johnson was the backup for Joseph and Shamar Stephen in 2019, and this season those two could be the Vikings starting tackles on the defensive line.

When asked what helped him develop, Johnson pointed to the Vikings veteran defensive lineman.

"I would say a lot of the guys, a lot of older guys, a lot of coaches, guys like that. I feel like we're all helping each other, we're all helping one another," the fourth-year Iowa product said. "We're a team, we all help one another."

D-line develops

The Vikings have had some of the best defensive line development in the NFL since coach Mike Zimmer and defensive coordinator Andre Patterson joined forces. They have seen a lot of mid-round draft picks take big jumps after a few years of development.

Griffen, who was the No. 100 overall pick in 2010, did it in his fifth season with the Vikings in 2014, when he was 27. He went from starting one game in his first four seasons to starting 16 games and recording a career-high 12 sacks.

For Hunter, the No. 88 overall pick in 2015, it was in his fourth pro season in 2018 when he started all 16 games and posted career highs with 14½ sacks and 72 tackles.

Johnson, who was selected No. 109 overall in 2017, will still be able to get coaching from Patterson, who has moved into a co-defensive coordinator position along with Adam Zimmer.

Patterson has been Johnson's defensive line coach his entire career and that should be a big plus if Johnson moves into the starting rotation.

"He is the one who has helped me get to where I am now," Johnson said about Patterson. "Just listening to him and just following what he's coaching."

Replacing preseason

When it comes to filling out the depth chart, another big challenge facing the staff is that — unlike baseball or basketball — football uses preseason games not just to warm up players but to make a lot of big decisions on the 53-man roster, especially with draft picks and undrafted rookie free agents.

Now the club will not have any preseason games while also having an NFL record 15 draft picks in camp.

Mike Zimmer said there's no doubt there will be some challenges but there are ways to work through them.

"Without preseason games we're going to have to set up situations throughout practice where, No. 1, we're going to have live contact, we're going to have to evaluate guys with some of our younger guys against our better guys to try to evaluate those players and those situations," the Vikings coach said. "You know, so, the evaluation part would probably be the biggest thing for a lot of these young guys."

How will the club create those kind of game situations for the new players?

"A lot of times in practice, coaches stand back there and go, 'Move to your left! Move to your right!' In preseason games they have to be out there and do it on their own. We're going to have to get these guys where the coaches aren't on the field — figure out how to go play this thing and understand," Zimmer said. "The game situations, we practice them all the time here with practice but there are things that come up in games that you can teach players about even during the course of the game. 'Alright there's seven seconds left, the ball is on the 10-yard line, this is where you line up.'

"There's so many different things you can get out of that. … The good thing about this is we can keep 16 practice-squad players, instead of the 10 or 12 that we have been able to, I think that is going to help them a little bit. We can try to get these guys going forward."

Jottings

• Gophers football coach P.J. Fleck spoke to the Big Ten Network about the Gophers' new football schedule that has them playing at Michigan State (Sept. 5), Michigan at home (Sept. 12), Iowa at home (Sept. 19) and at Wisconsin (Sept. 26): "We start with Michigan State at Michigan State and everyone knows coach [Mel] Tucker and his NFL history of what he's been able to do and building that program at Colorado and now he's here. Then we have three trophy games ­— three rivalry games right in a row. This might be the most vigorous September's Minnesota has seen in a long time."

• The Phoenix Suns have been the biggest surprise at the NBA bubble, going 4-0 with victories over Washington, Dallas, the Los Angeles Clippers and Indiana. Former Timberwolves point guard Ricky Rubio has been excellent, averaging 16.5 points, 6 assists and 4.3 rebounds per game. He's also shooting 44% from the field and 50% from three.

• Former Twins All-Star closer Brandon Kintzler now has that role with the Marlins, and through five games the righthander has three saves while recording a 1.80 ERA. He gave up a run Thursday vs. Baltimore but still helped Miami improve to 5-1.

• After being released by the Padres, former Twins second baseman Brian Dozier signed with the Mets and has played three games, going 1-for-8 at the plate.

Sid Hartman can be heard on WCCO AM-830 at 8:40 a.m. Monday and Friday and 2 p.m. Friday. • shartman@startribune.com