Pittman has earned 314 career catches, more than any player in their first four seasons in Colts history, passing Harrison's 311, per the team's official website.
On Sunday, the 26-year-old receiver caught 11 of 16 targets for 105 yards and the game-winning touchdown. Seven of his 11 catches went for a first down or touchdown.
The performance marked Pittman's second straight game with 10-plus catches and 100-plus receiving yards, joining Harrison in 2002 as the only Colts since at least 1970 to do so in two consecutive contests, per NFL Research.
"He's consistent every time he goes out there," Colts head coach Shane Steichen said of Pittman. "... (He) just came up back-to-back games with 100 yards receiving. Just the consistency that he plays with week in, week out, his preparation he puts into it, his toughness and his physicality, it's special."
Pittman has flown under the radar, much like the entire Colts operation into December. The wideout has generated 87 catches in 12 games, fourth most in the NFL, with 889 yards and four touchdowns.
Pittman has eight-plus receptions in five straight games (tied for the second-longest streak by a Colts player since at least 1970 -- only Harrison's six straight in 2002 is longer). The former second-round pick has eight-plus catches in nine games in 2023, the second-most such games in a season in Colts franchise history, behind only Harrison's 12 in 2002.
As he is heading toward free agency in the offseason, it's a pretty good year for Pittman to blast past all his career highs. He's proven an ideal target for Steichen's system as one of the most underrated route runners in the NFL.
"It's always good to come out and do it consistently," Pittman said. "Last week, it was another high-volume game. Just being there and making those tough catches. There were some tough catches that I should have made today that I would like back, but that's just how it goes. That's football. They're good players, too. I just have such a high standard."