EDEN PRAIRIE, Minn. — The Vikings held practice indoors Monday at Winter Park, getting their work in before a scheduled off day on Tuesday.

Minnesota practiced in helmets, shoulder pads and shorts for almost two hours. 

The Vikings split their first two preseason games, both on the road, but will square off against San Francisco at U.S. Bank Stadium at 7 p.m. (CT) on NBC's Sunday Night Football.

Here are three observations from Monday's session:

1. The head coach gets vocal

Vikings Head Coach Mike Zimmer began his NFL career as a defensive backs coach with the Cowboys more than 20 years ago. He revisited that position group on Monday, spending a portion of practice dishing out advice to his defensive backs during a coverage drill.

Minnesota had three defensive backs lined up as wide receivers, as Zimmer stood deep in the secondary and instructed them to run a variety of routes. Vikings defensive backs then worked on sticking with their man or passing off coverage to a teammate as Zimmer stood nearby.

Zimmer, who isn't always overly vocal in practice, then analyzed the play with the defensive backs as the group chatted about what we right or wrong in coverage.

2. Bringing their best 

Perhaps the most intriguing part of any Vikings practice is when the first-team offense goes up against the first-team defense, something that doesn't happen much, if at all, during regular-season practices.

With only a few preseason practices left, there is little time remaining for Riley Reiff and Danielle Hunter to tangle, Anthony Barr to race out and cover Dalvin Cook in the flat or Xavier Rhodes to shadow Stefon Diggs on a deep pass.

While the competition only makes the team better, the defense had its moment of pride Monday.

The offense was put in a situation where they trailed by seven points at their own 37-yard line with no timeouts and one minute, 42 seconds on the clock.

Quarterback Sam Bradford and the Vikings offense picked up one first down and moved the ball to the 50-yard line, but Minnesota's defense then shut them down. Cornerback Mackensie Alexander had a pass breakup on a third-down throw intended for Adam Thielen before Rhodes and safety Harrison Smith didn't let Diggs catch a fourth-down attempt down the sideline.

3. Quick decisions

The 49ers defensive line rotation features three players who were taken in the first round in each of the last three seasons — Arik Armstead in 2015, DeForest Buckner in 2016 and Solomon Thomas in 2017.

With the trio coming to town on Sunday, the Vikings solved their own defense's speedy pass rush Monday by using quick passes in team drills.

Cook, Latavius Murray and Jerick McKinnon were involved in screen and swing passes while Bradford hit a handful of wide receivers and tight ends on shallow routes as well.