The NFC Divisional Playoff represented Alexander's first game action since Week 10, during which he tore his pectoral muscle and eventually was placed on injured reserve. He remained very close with the team, though, adding energy on the sideline during games, but he contributions on the field were missed.
"There's so much more swag and confidence when he's out there," 49ers linebacker Fred Warner said. "He's great. I love being out there with him. He's a leader. There's a lot more to it than him just being a good ballplayer out there. His value is huge for the team."
49ers coach Kyle Shanahan noted that even when he's not racking up defensive statistics, Alexander affects the play on the field.
"Having Kwon out there, the times I'm looking up watching him, the way he flew around, made some plays on the screens," Shanahan said. "Even when he flew and missed the guy on the screen, he makes the back have to come to a complete stop and cut back the other way, then our pass rushers can get there."
Alexander's return coincided with Dee Ford and Jaquiski Tartt also being back in the lineup. The defense was re-energized, and held Vikings running back Dalvin Cook to nine carries for a season-low 18 yards and six receptions for 8 yards.
The Vikings' offense had just seven first downs and 147 total yards, 21 of which were on the ground.
Alexander wasn't surprised at all that the 49ers shut down Cook, who had five 100-yards games this season and posted 1,135 yards over 14 games. Alexander believes the 49ers' defense can even get better.
"We were able to be us," Alexander said. "Once we do that, we can go out there and have fun, and when we play together as a team, it's hard to beat us. That is all we have to do and we are going to go far.
"We were just being legendary, being ourselves. We work hard. We worked hard this week. Everybody came to work ready, with a lot of excitement, a lot of energy, and it showed out there on the field. That is how we did that."
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Most of all, Alexander was overjoyed to be in front of the fans at Levi's Stadium.
"The Faithful is crazy," he said. "The fans, I love them. They were out there. They were supporting us. We had to go out there and do our job for them, and we got the job done.
"Man, it felt amazing. I'm so happy."
Kwon Alexander's value to 49ers not measured in stat sheet vs. Vikings originally appeared on NBC Sports Bay Area