SANTA CLARA — This just in from Greg Papa: “I am doing great.”

Because he is, Papa will be back doing play-by-play duties for the 49ers’ radio broadcast of tonight’s NFC showdown with the Seattle Seahawks at Levi’s Stadium.

Papa, 63, has been on hiatus this season while battling leukemia. He had planned on returning for last Sunday’s 42-38 home win against Chicago but delayed his comeback until this game.

Whoever wins between the 49ers (12-4) and the Seahawks (13-3) will secure the NFC playoffs’ No. 1 seed and the NFC West title. Those were the same stakes in the 2019 regular-season finale, which the 49ers won in Seattle en route to the Super Bowl, all with Papa enjoying his first season as the voice of the 49ers.

Papa has kept close watch of this season’s improbable path to the playoffs, and even though he’s stayed out of the radio booth and off the practice field, he’s continued his KNBR 680-AM show with Greg Silver.

Tonight, he’ll be back in the booth with longtime sidekick Tim Ryan for KNBR’s broadcast.

Papa still is awaiting a bone marrow transplant, though doctors have found perfect matches with his older brother, Ron, and younger sister, Judy. He was diagnosed in July and hospitalized for 23 days, of which he recalled: “My eyes were yellow, my skin was yellow. I lost 20 pounds in three days. I didn’t know if I was going to live at that point.”

Papa has since undergone immunotherapy and two cycles of chemotherapy.

Guy Haberman has covered for Papa the majority of games this season, including Sunday’s back-and-forth thriller against Chicago that featured six 49ers’ touchdowns — or, as Papa might say tonight, “Touchdown SAN-FRAN-CISCO!”