In return, the Colts will send a seventh-round draft pick in 2014, according to the NFL Network. That means San Francisco is slated for 13 picks next spring.
In a corresponding move, San Francisco is trying to sign former Seahawks receiver Chris Harper, who the team was hoping to put on its practice squad, according to CSN Bay Area. ESPN reported Harper's signing was a done deal.
Harper, a rookie from Kansas State, was taken in the fourth round by Seattle - five spots ahead of where the 49ers selected Quinton Patton. He was released Saturday. The 49ers are hoping to add Harper to the 53-man roster, giving them six wide receivers. He would join Anquan Boldin, Kyle Williams, Marlon Moore, Quinton Patton and Jon Baldwin.
Johnson made the team after spending most of training camp on the bubble. His chances at cracking the roster seemed slim before Parys Haralson was traded to the Saints. Johnson would then have a standout performance in the preseason finale against the Chargers, notching two sacks and recovering his own blocked punt in the end zone for a touchdown.
"We appreciate Cam's efforts since joining our team a year ago," general manager Trent Baalke said in a statement. "He has continued to grow as a football player and we wish him all the best with his new opportunity in Indianapolis."
Johnson was taken in the seventh round last season out of Virginia. He spent the majority of the season on the practice squad before being promoted to the active roster in late-December. He totaled seven tackles and three sacks this preseason.
With three outside linebackers backing up Aldon Smith and Ahmad Brooks, the 49ers had overlapping talent with Dan Skuta, third-round pick Corey Lemonier and Johnson. It was likely one of the three backups would not have been one of the active 46 players on game day.
It's also unlikely Harper suits up on game days, but he adds depth and talent to perhaps the weakest position on San Francisco's roster with Michael Crabtree and Mario Manningham sidelined for at least the first six weeks of the season. There is no timetable for Crabtree's return from his torn Achilles, but he will be on the PUP list going into the season.
The 49ers traded former first-round pick A.J. Jenkins to the Kansas City Chiefs for fellow first-rounder Baldwin Aug. 19. Baldwin played well in his limited action during the final two preseason games and is still adjusting to the offense. But he possesses the physical attributes San Francisco has coveted in receivers of late.
Both Baldwin and Harper are physical receivers, unlike Jenkins, who are more apt to stand up to press coverage from big, physical corners.
If Harper doesn't suit up with the active 46 for the season's first six weeks, the 49ers could put him on the practice squad when Manningham returns. The team signed undrafted rookie wideout Chuck Jacobs to the practice squad Monday.
Harper originally went to Oregon as a quarterback, but switched to wide receiver early on. He went on to transfer to Kansas State, making 122 catches for 1,725 yards and 12 touchdowns in his three seasons for the Wildcats.
11:53 A.M: CSN Bay Area reports Harper's signing is official, according to a source.
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