Updated

By Ben Klayman

DETROIT (Reuters) - The National Football League prodded Toyota Motor Corp to edit a television commercial, removing an image of a helmet-to-helmet tackle at a time when the effects of concussions have come under heavy scrutiny, representatives of both sides said.

The Japanese automaker, one of the largest corporate advertisers, changed the TV ad after the U.S. sports league complained and warned that the spot would not be allowed to air during its highly watched games.

The NFL's request, a rare occurrence in the advertising world, reflected the sensitivity of the topic within the league and the lengths it will go to to protect its image and position as the country's most popular sport.

"The NFL saw it on Monday Night Football and the next morning we got the call," Tim Morrison, corporate marketing communications manager for the Toyota division in the United States, told Reuters. "They weren't happy.

"I'm sure if they'd had their druthers, we'd have pulled the spot," he added. "We weren't pulling the spot. We couldn't. But we never intended the spot to irritate the NFL."

In the ad, as images of football players and brain scans flash by, Wake Forest University professors discuss the potential use of Toyota technology to help to understand and prevent brain injuries.

Viewers did not connect the tackling with the NFL, but the commercial was re-edited to remove the offending image despite grumbling by some at the automaker, Morrison said. The ad remains in rotation.

"It was just 'please, don't show it,' so we just tweaked it and took the image out," he said.

NFL TAKES ACTION

The issue of concussions in sports has become a hot topic in the United States, in part due to violent hits by players in NFL games. The league has taken new steps to protect its players from concussions, and remains sensitive to the issue.

"From time to time, we will address an ad that portrays our sport unfairly," NFL spokesman Brian McCarthy said.

The commercial, featuring crash dummy software Toyota uses to help prevent injuries in auto accidents, is one of three created with Saatchi & Saatchi, a unit of France's Publicis Groupe.

The "Ideas for Good" campaign, created to tout Toyota's technology about a year after a series of recalls hurt U.S. sales, was launched in early November with the football ad, which can be viewed at www.toyota.com/ideasforgood .

Toyota aired the ad during NFL games on the week of November 8 because that was where the most eyeballs were.

The NFL's 2010 regular season reached almost 208 million unique U.S. viewers, the highest total ever, and NFL games for the first time ever were the most-watched program each week during the season, the league said, citing Nielsen data.

Automakers' ads have long been a staple during NFL games. During this year's Super Bowl, a record number of automakers are expected to show ads after spending almost $30 million in 2010 according to Kantar Media.

Toyota spent more than $807 million on U.S. advertising through the first nine months of 2010, up 28 percent from the prior year, Kantar said. That made Toyota the No. 2 spender in the industry behind General Motors Co.

After seeing the Toyota ad, the NFL complained to its network partners -- CBS, Fox, NBC and ESPN, Morrison said. Those concerns were brought to Saatchi and then Toyota.

All the networks declined to comment, but one ad buyer said the request was unusual if not surprising.

(Reporting by Ben Klayman in Detroit, editing by Matthew Lewis)