The coaches at the NFL Europe training camp in Cologne obviously expected British sprinter Dwain Chambers to be fast.
Chambers is ready to turn his back on athletics for NFL Europe
But they were taken aback by quite how quick he was.
The true extent of his blistering pace became apparent when he was put through a simple drill at the start of the one-week camp in November.
The idea was simple - to catch the ball, run down the middle of the field and try to evade the onrushing defenders.
"Normally the receiver will be hit by the defenders," David Tossell, director of public affairs for NFL International, told BBC Sport.
"But Dwain was so fast he pulled away from two guys you would expect to get him. It was really impressive."
Chambers is deadly serious about pursuing a career in American Football.
On Tuesday, his agent told BBC Sport that the 28-year-old was ready to turn his back on athletics in order to play in NFL Europe.
And his ambitions don't stop there. The average earnings for a player in NFL Europe are only £5,000 to £8,000 per three-month season and the former European 100m champion has his sights set on the NFL proper in America, where first-year professionals are paid a minimum salary of £130,000 and can go on to earn many millions more.
Unsurprisingly, Tossell says Chambers was "easily the fastest player" at the November camp. But he will need far more than raw pace if he is to fulfil his initial ambition of becoming a wide receiver for one of the five NFL Europe teams.
NFL Europe factfile
Feeder league for the NFL
Season runs from March to May
Each team has 48 players (42 US and 6 international)
Only one international player has made it from NFL Europe to NFL - Constantin Ritzmann
Catching skills, strength, determination, teamwork and tactical appreciation - none of which necessarily come naturally to an athlete - are all equally important.
Yet Tossell says the early signs are promising for Chambers.
"The thing that's really impressed our guys is how determined he is," Tossell said.
"He had turf toe on both feet and had hurt his ankle, but didn't sit out any of the practices. The thing the coaches in Cologne wanted to find out was how he would react when hit. And he picked himself up and carried on.
"He did better than they'd expected and was tougher than they thought he would be."
NFL Europe is a feeder league for the NFL and consists of six teams - Frankfurt, Berlin, Cologne, Dusseldorf, Hamburg and Amsterdam.
Each team has 48 players - 42 of them young Americans from NFL teams who are sent to Europe to gain experience and the remaining six "international players".
NFL Europe invited a total of about 270 players to three pre-Christmas training camps as an initial step in finding these international players.
The first, which Chambers attended, was in Cologne and the next ones will be in Mexico and Japan.
Dwain is up against young, hungry guys who have played the sport all their lives
The best 70 or 80 will then be invited to a six-week training camp in Florida in March before 48 are offered contracts with teams.
Although Tossell is encouraged by Chambers' early showings, he says it will still be very difficult for him to make a career in gridiron.
"He was always a casual fan of American Football and doesn't know a lot about the nuances and tactics of the game. He's up against young, hungry guys who have played the sport all their lives.
"And the team ethic of the sport is very different from being an athlete."
Commercial considerations are also unlikely to help Chambers' cause. Because five of the teams are based in Germany and the other in Holland, his inclusion would have little "bums-on-seats" appeal.
As for Chambers' ultimate ambition of reaching the NFL proper, it's worth considering one stark fact - only one "international" player has ever come through the feeder league to forge a career in the NFL.
That was the German Constantin Ritzmann, who played for the Buffalo Bills and Atlanta Falcons but is not currently on the roster of an NFL team.
"I was surprised and pleased when Dwain first rang me to say he wanted to come along to the training camp," Tossell said.
"This is something of an experiment, to see if a cross-over athlete can make it in NFL Europe.
"But we made sure we sat down with him and explained how difficult it would be. There are huge odds against him making it and we made sure he understood that."
Chambers will find out if he has been invited to the Florida training camp either shortly before or after Christmas.
That will be the first step on a journey that he hopes will end up in the NFL or even at the Super Bowl, like his role model Renaldo Nehemiah, who was the 110m world record holder before going onto forge a successful career with the San Francisco 49ers .