SANTA CLARA, Calif. -- The bye week was good to the San Francisco 49ers, who are about as healthy as they have been since Week 3 at the most opportune time.
For Saturday's NFC divisional playoff game against the Minnesota Vikings, the Niners are welcoming back four key players from injury.
Safety Jaquiski Tartt (ribs), defensive end Dee Ford (quad/hamstring) and guard Mike Person (neck) are active to face Minnesota. Linebacker Kwon Alexander (torn pectoral) also was activated from injured reserve Friday and is available for Saturday's game.
Like Houston Texans defensive lineman J.J. Watt, Alexander is returning from what is normally a six-month injury in a little more than two months. He wore a blue no-contact jersey in practice all week and made it through the week without any issues.
The biggest remaining question is how much Alexander will play. Earlier in the week, Shanahan indicated Alexander could be a bit restricted from his usual workload and rookie Dre Greenlaw would continue to get plenty of playing time.
Getting Alexander back is considered a big lift for the defense, which has missed his high-energy style since he suffered the injury on Oct. 31.
"Having Kwon is exciting," defensive coordinator Robert Saleh said. "He brings a lot of juice, a lot of energy. Even in practice, if there's a lull in practice, he's the first to speak up to get guys going. From a coach's view, it's very beneficial to have a guy who regardless, whether it's bad or good, his voice is projecting positive energy and trying to get people rolling. To have Kwon, aside from the player, just from the juice and the energy he brings and what he does for everybody around him, is really priceless."
Adding Tartt and Ford is also beneficial for the Niners, who have been without Tartt since Dec. 1 and Ford since Dec. 8. Tartt practiced in the week leading up to the season finale against Seattle and wore a no-contact jersey like Alexander. He has had no restrictions since and was not listed on the injury report all week.
Ford has had a series of stops and starts stemming from a knee issue that's bothered him all year and quad and hamstring injuries that cropped up late in the season. In Ford's absence, the Niners defensive front has still generated pressure but hasn't gotten home nearly as often.
According to ESPN Stats & Information, the Niners had 24 sacks on 164 snaps with end Nick Bosa and Ford on the field together this season. They had 24 sacks on 801 snaps on all other plays.
"Having him out there with all of us really, really affects blocking schemes," defensive tackle DeForest Buckner said. "It's just another really good pass-rusher out there. ... Having him and Nick out there, even having Nick on the edge, they can't really slide one way or another, they have to pick and choose."
Shanahan said a decision on whether Person will start at right guard has not been made. Daniel Brunskill has started in Person's stead the past two games.