"We have filled a need with one of the top players in football at his specialty, returning punts and kicks," Rams coach Scott Linehan said. "Dante will fit nicely on our special teams and can be utilized as a receiver in certain situations."
The trade could have draft-day implications. The Rams had expressed strong interest in Ohio State's Ted Ginn Jr., as much for his return ability as for his resume as a receiver. St. Louis also has several needs on defense.
As part of the trade, the teams swapped positions in the third round -- the Chiefs moving up to 82nd overall, the Rams down to 84th.
"We have to get younger, and the only way you can do that is through the draft," Chiefs coach Herm Edwards said. "You're going to have to give up something to get something."
The trade also gives Kansas City seven draft choices.
"We feel that it's always important to have at least seven draft picks," Chiefs president Carl Peterson said. "Hopefully, we'll be able to acquire another one or two in the days to come."
The Rams have struggled for years on kick returns. Last season, St. Louis averaged 7.8 yards per punt return. Only five teams were worse. The Rams were 26th in kickoff returns, averaging 21.3 yards.
The 28-year-old Hall has returned 11 kickoffs and punts for touchdowns in his seven-year career, including four (two kickoffs, two punts) in 2003. Brian Mitchell holds the record with 14 kick-return touchdowns, followed by Eric Metcalf with 12.
Hall also needs one more kickoff return for a touchdown to break the record of six he shares with Ollie Matson, Gale Sayers, Travis Williams and Mel Gray.
Hall was the NFL's top returner from 2002-04. His production declined the last two seasons, though he had one punt return for a touchdown last season, on Oct. 1 against San Francisco.
In 2003, he averaged 25.9 yards per kickoff return and 16.3 yards per punt return.
Last season, Hall averaged 22.8 yards on 53 kickoff returns and 8.9 yards on 27 punt returns. He also caught 26 passes, two for touchdowns.
For his career, all of it with Kansas City, Hall averaged 24 yards per kickoff return and 10 yards per punt return.