The 13-3 San Francisco 49ers earned the No. 1 seed in the NFC and a first-round bye, which opened the door for one of their best players to return from injury. On Friday, the 49ers announced that they had activated linebacker Kwon Alexander from injured reserve, and placed defensive lineman Kentavius Street on injured reserve. 

Alexander, who signed a massive deal with the 49ers last offseason, tore his pectoral in the team's Week 9 victory over the Arizona Cardinals on Halloween. He was an important part of the defense up to that point, and he recorded 34 combined tackles, four passes defensed, one interception and half a sack in eight games played. The 49ers did not foresee Alexander doing this well in his recovery, and he is now cleared to suit up for San Francisco's first postseason game.

The Pro Bowl linebacker participated in the 49ers' bye-week practice last week, and the team then opened his practice window to return from the injury.

Alexander isn't the only star defenseman who made a miraculous recovery to return for the postseason. Last Saturday, Houston Texans defensive lineman JJ Watt suited up against the Buffalo Bills after tearing his pectoral muscle in Week 8. He recorded one tackle and one sack in the 22-19 victory. It's unlikely that Alexander will immediately return to his three-down linebacking role, but San Francisco is happy to have him back on the field nonetheless. 

The 49ers kick off against the Minnesota Vikings, who took down the New Orleans Saints in the wild-card round, this Saturday at 4:35 ET.