Stuart Lancaster has completed a three-day stint with NFL franchise the Atlanta Falcons, providing a rugby perspective on tackling.
The former England head coach was invited to analyse a match against the Washington Redskins last season and then outline alternative skills and drills used for safe and effective defence.
Concussion is an ongoing concern in the NFL, partly as a result of the tackle technique taught to children taking up the game and which persists at a professional level.
"In rugby you are coached on effective tackling technique from a young age and I tried to pass on some of that to American football as the two are similar in many ways," Lancaster said.
"There were lots of areas of good practise in American football, but also one or two areas that could be improved upon. The defensive coaches took on board some of the pointers."
Advice was also offered on tackle completion to prevent opponents from gaining extra yards.
"In a rugby game they are tackling constantly so we thought there was a lot to gain from Stuart," Falcons head coach Dan Quinn said.
Lancaster was replaced by Eddie Jones after last autumn's World Cup and is currently under consideration for coaching posts with Australian Super Rugby franchises the Reds and Force.
The Cumbrian has been invited by the Football Association to sit on an advisory board to provide background on how English rugby's highly successful junior player development system has evolved in the last 10 years and he is also on the UK Sport's review panel for their investigation into British Cycling.