The 21-year-old has 86 rushing attempts since replacing an injured Joe Flacco in Week 11, the most by any quarterback through his first five career starts in the Super Bowl era. Only running backs Saquon Barkley, Derrick Henry, Ezekiel Elliott, and Gus Edwards have more yards on the ground than Jackson over the past five weeks.
"I think that's all going to work out over time," Harbaugh said Monday, according to Jamison Hensley of ESPN.
There are some in NFL circles who are wary of the dangers that run-happy quarterbacks face. The league's all-time leading rusher among QBs, Michael Vick, advised Jackson to "proceed with caution," after his second start.
Jackson debuted as a starter with 26 carries in a 24-21 win over the Cincinnati Bengals. His 18 attempts in Week 15 was his second-highest single-game mark of the season and upped his season total to 114 attempts for 566 yards and three touchdowns. He's compiled a 4-1 record in his starts.
Harbaugh insists that plays in which Jackson takes a knee to kill the clock is padding those numbers.
"I think when you look at all that stuff, take it into account," Harbaugh said. "But to me, over time, that will sort itself out."