The NFL has confirmed the referee assignments for the conference title games in an announcement that should be of particular interest to the San Francisco 49ers' secondary.

San Francisco's NFC Championship Game against the Detroit Lions will be refereed by Clete Blakeman.

Blakeman has only refereed one 49ers game this season. That came way back in Week 4 in San Francisco's blowout win over the Arizona Cardinals.

San Francisco was penalized four times for 21 yards in that game. The Cardinals had nine penalties against them for 55 yards.

Though that disparity was in the 49ers' favor, a more pertinent stat concerns Blakeman's season-long performance.

Per NFLPenalties.com, only three referee crews called pass interference more often this season than that of Blakeman, whose games saw flags for that foul thrown 20 times. His regular-season crew also called defensive holding 15 times, the second-most in the NFL.

His team on Sunday will be made up of officials from a variety of different crews, but does include the down judge from his regular-season crew and a line judge from the crew of Alex Kemp, which called DPI 21 times.

Those are worrying numbers for a 49ers secondary that was flagged three times for DPI in their divisional round win over the Green Bay Packers. Cornerback Ambry Thomas was flagged twice, while safety Tashaun Gipson was also called for it.

It will be interesting to see if the 49ers stick with Thomas following a chastening display that also saw him give up five catches on five targets for 74 yards, but the assignment of Blakeman makes it even more imperative the secondary as a whole produces a disciplined performance.

49ers face bigger title game challenge after Lions roster move

Another weapon to think about.