Johnson's contract is worth $64 million, with $27.2 million fully guaranteed, ESPN's Chris Mortensen reports.
Johnson and the team agreed to terms and signed the contract early Friday, said Lions executive vice president Tom Lewand. He signed the deal just in time for an 8:30 a.m. practice, where he was out catching passes. Moments after signing his contract, the rookie wide receiver found himself on the first team during a two-minute drill.
"I wasn't surprised. I was expecting to be out there with the first team," Johnson said. "That's why they picked me at No. 2.
"It's good to be on the field and not be dealing with contract stuff any more. At first, I was trying to be patient, but it's been pretty nerve-racking for the last few days."
Johnson's arrival came at a perfect time for the Lions, its first public workout.
"We choreographed that pretty well, didn't we?" Lewand joked.
A large cheer went up once the 500 fans in attendance realized Johnson was on the field, and more applause followed every catch he made in the two-hour practice.
"I thought today went pretty well," Johnson said before signing autographs. "I made some mistakes, but I was able to retain a lot of what I picked up in [offseason team activities]."
Johnson was regarded by some as the best player in the draft
after catching 78 passes for 1,202 yards and 15 touchdowns during
his All-America junior season at Georgia Tech. He won the
Biletnikoff Award, given to the nation's top college receiver.
The Lions made room for Johnson on the roster by placing
quarterback Drew Stanton -- a rookie second-round pick out of
Michigan State -- on injured reserve, meaning he's out for the
season. Stanton had arthroscopic knee surgery earlier in the week.
"He's a quick study, so we put him right out there with the
ones in the two-minute drill," Lions coach Rod Marinelli said of
Johnson. "We've got some receivers whose legs are gone, and
Calvin's fresh, so he's going right into the fire."
The Lions, 3-13 last season, in April made Johnson the fourth receiver taken with their first pick in the past five drafts.
The Lions are 24-72 and have missed the playoffs every season
since Millen joined the front office in 2001. The soft-spoken
Johnson figures to get ample opportunities in offensive coordinator
Mike Martz's pass-happy scheme.
"I have a very good feeling about this group," Marinelli said. "We've got some very special players on this field."
Furrey and Williams are equally confident after working with
Johnson during offseason practices.
"No one is going to be able to stop us when we are all out on
the field," Furrey said. "People are excited about Calvin, but
they don't even know what they've got yet. He's going to be one of
the top receivers in the league in a couple years."
Marinelli also expects Johnson to affect Detroit's rushing
"When we have those three men on the field, and especially when
we add Shaun McDonald as a fourth receiver, it is going to force
defenses to spread themselves wide," he said. "That's going to
open up a lot of room for Tatum Bell or Kevin Jones."
Information from The Associated Press was used in this report.