Greg Cosell explains how the 49ers might attack the Vikings and what to expect from Kyle Juszczyk

Greg Cosell says the San Francisco 49ers offense operated out of 21 personnel, which features two backs and one tight end, in about 45 percent of its snaps during quarterback Jimmy Garoppolo's five starts last season. The team used the personnel grouping more than any other NFL team.

The NFL Films executive producer and analyst broke down on ESPN's NFL Matchup how head coach Kyle Shanahan uses 21 personnel to attack opposing defenses. The breakdown was shared Friday on Twitter.

The personnel grouping gives offenses the option to use the tight end or a back in the passing game, as Cosell showed in the example with fullback Kyle Juszczyk. It explains why Shanahan is so insistent on having versatile players on his roster. It creates tough decisions for opposing defensive players when they have to worry about both the run and the pass.

Cosell joined KNBR on Friday and shared what he expects to see on Sunday during the matchup between the 49ers and the Minnesota Vikings.

"I would expect the Niners to play a lot out of 21 personnel because that will put (Vikings linebacker) Ben Gedeon on the field," Cosell shared. "He's their third linebacker when they play in their base 4-3. The thing is, last year, he was only on the field for less than 25 percent of their defensive snaps.

"So, now you go with 21 personnel, he's likely to be on the field as their third linebacker. You kind of make Minnesota play a little bit out of their comfort zone where the Niners play in their comfort zone because, in Garoppolo's five starts, they were in 21 personnel with a fullback, Juszczyk, about 45 percent of their snaps."

When the 49ers want to get three receivers on the field against the Vikings, Cosell thinks fans might see a little wrinkle on offense. He wouldn't be surprised to see the 49ers with just Juszczyk in the backfield when the offense goes 11 personnel, which features just one back and one tight end.

"I'm not saying every time they're in 11, no," Cosell explained, "but I think there will be 11 personnel snaps in which Juszczyk is the single back because he's such a good receiver."

You can listen to the entire conversation with Cosell below. If you haven't watched the 21 personnel breakdown video above, be sure to do that as well.