Jackson fills a much-needed role as a deep-threat wide receiver on an offense that will feature quarterback Matthew Stafford next season.
"We're always trying to add some juice, and we'll see what the next month and a half entails," Rams coach Sean McVay said Friday when asked if the team needed to find a wideout to stretch the field for Stafford.
"Every offense probably in the NFL would love a deep threat, right?" Rams general manager Les Snead said, answering the same question. "If I added to that, it doesn't necessarily have to be someone that catches one deep ball a game; those can be low-percentage throws. But when you definitely have skill players with juice, that can threaten the top shelf of the coverage."
Jackson's deal is for one year, the team said.
A three-time Pro Bowl selection, Jackson has recorded the most 60-plus-yard touchdowns (24) in NFL history. The 34-year-old, who is entering his 13th NFL season, ranks sixth all time in yards per reception (17.4).
In Los Angeles, Jackson reunites with McVay, who served as his offensive coordinator for three seasons with the Washington Football Team from 2014 to 2016. Jackson joins a receiving corps that includes Robert Woods, Cooper Kupp and second-year pro Van Jefferson. The Rams also utilize tight end Tyler Higbee in the passing game.
"We need to be more explosive offensively, but we've been a really explosive offense with Cooper Kupp, Robert Woods and Higbee being centerpieces of it; those guys are going to continue to be that," McVay said. "But when you talk about opportunities, you have to call plays that give you an opportunity to be explosive, and that's where my contribution is. Anytime that you have guys that can do that, that definitely is a benefit."
Jackson became a free agent when he was released by the Philadelphia Eagles in February.
Jackson's return to Philadelphia was limited by injuries since he was acquired from the Tampa Bay Buccaneers in 2019, reuniting the deep-threat receiver with the team that drafted him.
The excitement of the reunion was fueled by two touchdowns of longer than 50 yards in the 2019 opener against Washington, but Jackson wound up playing in just three games that season because of a core muscle injury. Jackson then missed 11 games in 2020 with an injured ankle.
Overall, he has 612 receptions for 10,656 yards and has scored 60 touchdowns (including four rushing and four punt returns). He was selected by the Eagles in the second round of the 2008 draft and played six seasons in his first stint with the team, before joining Washington in 2014.