CHARLOTTE, N.C. -- In the days before the scouting combine, Bob Hayes changed the NFL.

An Olympic gold medalist as a sprinter in 1964, "Bullet Bob" was a seventh-round pick of the Dallas Cowboys and kept coaches up at night designing exotic zone defenses to keep him from beating them over the top.

“Scary,” then-Cowboys director of player personnel Gil Brandt said. “The speed he had was ... well, frankly, it was beyond belief.”

That kind of speed is much more prevalent in the NFL now, says the Hall of Fame executive, now 87 and a radio analyst. Brandt looks no further than the Kansas City Chiefs winning the Super Bowl last season with three receivers who clocked 40-yard dash times of 4.29 to 4.43 seconds coming out of college.

Speed at receiver is one of several reasons Brandt believes the Carolina Panthers, despite being inexperienced and led by a first-year NFL coach in Matt Rhule, could be a surprise team this season.

Looking at the top three receivers, the Panthers' trio ranks among the fastest in the league. Curtis Samuel ran the 40 in 4.31 seconds coming out of Ohio State. Robby Anderson was clocked at 4.36 seconds coming out of Temple, and DJ Moore ran a 4.42 at Maryland.

That’s an average of 4.36 seconds, comparable to the 4.35-second average of the Chiefs' trio: Tyreek Hill (4.29), Mecole Hardman (4.33) and Sammy Watkins (4.43).

Carolina also has the NFL’s most versatile running back in Christian McCaffrey, who ran the 40 in 4.49 seconds coming out of Stanford.

Panthers linebacker Tahir Whitehead believes that kind of speed will keep opposing coordinators and defenders working overtime.

“It stresses them out,” Whitehead said. “[Those] guys are blazing fast. We look at them like, 'Golly, we've got to go up against that in practice? We have to match up with them?'

“I don't think there's too many other teams that have that type of speed with finesse and hands."

More than just speed

Brandt left the 2017 NFL combine blown away by Samuel.

“I said this guy has a chance to be the Offensive Rookie of the Year,” he said.

That didn’t happen. Samuel caught only 15 passes for 115 yards as a rookie as injuries limited him to nine games. He caught 39 passes in his second season and 54 in his third, overshadowed by first-round pick Moore.

“Moore is a guy, if you raced him in shorts and football shoes, he couldn’t beat Samuel,” Brandt said. “But if you put the uniform on, then he’s going to win. He’s like Jerry Rice.”

Rice didn’t display blazing speed at the 1985 combine, posting a time of 4.58 in the 40. Where he excelled and what helped him become the NFL’s all-time leader in receiving yards (22,895) was his ability to maintain speed in pads, running routes.

“Like Hayes, he was a home run threat every time,” Brandt said. “When you can get speedy receivers who can sync their hips and are able to run all the routes, that’s what you’re looking for.”

Brandt says Cincinnati’s A.J. Green epitomizes the ideal receiver today. He ran the 40 in 4.48 seconds in 2011, but ran a 4.21 in the short-shuttle and 6.91 in the three-cone drill.

Samuel ran a 4.33 in the short-shuttle and 7.09 in the three-cone drill.

“Green’s got that combination you’re looking for, the speed and ability and change of direction that make him a threat,” Brandt said.

That’s where Moore has an edge on Samuel. He ran the short-shuttle in 4.07 seconds and the three-cone in 6.95 seconds. He already has established himself as a budding star with 87 catches for 1,175 yards last season.

“A lot of guys are fast, but they have to slow down to run a route,” Brandt said. “Sometimes speed is a little misleading.”

Speed also is something you can’t replace. Just the threat of it opens up the offense. Ted Ginn Jr.’s track speed was a major factor for the Panthers in 2015, when the team led the NFL in scoring with 31.3 points a game and Cam Newton won the MVP.

Hayes did that for Dallas. He never had more than 64 catches in a season, but averaged an amazing 20 yards a catch in 11 seasons and caught a touchdown every 5.22 completions. Kansas City’s Hill, by comparison, averages 14.6 yards per catch and a touchdown every 8.7 receptions.

“Hayes changed the way the game is played,” Brandt said.

Separation

Samuel had one of the best seasons of any receiver the past three years in terms of separation, averaging 0.24 yards in 2019. That’s slightly lower than Hill’s average of 0.25 in 2018.

Samuel's goal is to turn that into consistent productivity. A quarterback change could help him improve on last season's numbers.

Newton had the NFL’s highest rate of uncatchable passes (34.2%) through the first two games of 2019, per Pro Football Focus, before being shut down because of a Lisfranc injury. His first replacement, Kyle Allen, threw 16 interceptions and 17 touchdown passes.

Rookie Will Grier, who started the final two games, completed 53.8% of his pass attempts.

That’s why the Panthers signed Teddy Bridgewater to a three-year, $63 million deal. He completed 67.9% of his attempts last season in going 5-0 for the New Orleans Saints while Drew Brees was injured.

Panthers offensive coordinator Joe Brady, who coached Bridgewater for one season in New Orleans, will run a variation of the Saints' offense mixed with what he did last season for national champion LSU, which could mean lots of opportunities for the receivers.

LSU had two receivers gain more than 1,500 yards last year, and two more who gained more than 500.

They were fast, too. Justin Jefferson, who went to the Minnesota Vikings with the 22nd pick of the draft in April, ran a 4.43 40 at the combine. Derrick Dillon, now with the New York Giants, ran a 4.29 at LSU’s pro day.

With the Panthers, Anderson said he has never has been around a faster group of receivers.

“It's a huge advantage,” he said.

Samuel said having three receivers with deep-threat ability will open up more underneath routes for McCaffrey, who had 116 catches last season, and tight end Ian Thomas.

“It opens up so much more when you've got speed because a lot of guys start to back up and create that cushion,” Samuel said.

Whether teams respect Bridgewater’s ability to complete deep passes might be the biggest question. According to Pro Football Focus, he ranked 19th in the NFL last year on deep throws with a 46.7 completion percentage. He averaged 15.7 yards per attempt on those throws.

The deep ball doesn’t seem to concern Bridgewater or any of the Panthers. Samuel said there are many ways to get the ball into hands of speedy playmakers.

“All we’re going to do is focus and keep going out there each and every day,” Samuel said. “And we’re going to do great.”

Track team

Speed at receiver was a staple of Rhule’s offenses at Baylor.

“We had guys that would scrimmage on a Saturday afternoon and then leave and go over to track and win the 100-meter dash,” said Rhule, whose 2019 team averaged 33.6 points a game. “We were a track team, so we changed our entire offensive identity.

“We always had three receivers on the field, if not four. So we were really fast, really fast at Baylor. And coming here now, I think we have a really nice set of fast guys on the outside. That makes me feel very comfortable.”

Bragging rights for speed are a subject of dispute among the players. Cornerback Donte Jackson, who ran the 40 in 4.32 seconds at LSU, will tell you he’s Carolina’s fastest player. He laughs at the suggestion rookie cornerback Troy Pride Jr., who ran a 4.40 40, is faster.

Bridgewater will tell you he’s fast enough to be part of a Carolina 4x100 meter relay team that includes McCaffrey, Samuel and Anderson.

Rhule isn’t so sure.

“Teddy has a high opinion of himself in terms of speed,” he said.

But Rhule loves Carolina’s overall speed, particularly at receiver. He already has challenged Moore to step up his game “and be that dominant, physical, go-to receiver.”

“Take the best matchup of the other team’s best corner and just dominate,” Rhule said.

Moore concedes he’d be the slowest in a race with Samuel and Anderson. Samuel concedes nothing. In this world of social distancing, when asked which receiver would distance himself the furthest from the other, he laughed and said, “That’s a funny way to put it. I'm never gonna say I'm not the fastest.”

His goal, however, isn’t to be the fastest. It’s to use that speed to help the Panthers win, as Hayes did with the Cowboys more than 50 years ago.

“When we line up against other teams,” Samuel said, “... defenses, they know they’ve got to get on it.”