Shaun O’Hara had just arrived at Giants Stadium for practice Thursday morning when a teammate said he had seen an item about Gene Upshaw’s death on television.

“I thought it had to be a hoax because it was all of a sudden,” said the New York Giants center, who also is the team’s union representative. “I tried to search online and find some more information. When I discovered it was true, it was very sad to hear.”

It was the same for most of the 2,400 players on NFL rosters as well as for owners, coaches, league officials and team administrators. It wasn’t just the fact of Upshaw’s death but the shock of it. Until recently, when people began to notice he had lost weight, no one thought that the 63-year-old Hall of Fame guard was in anything but perfect health.

In fact, Upshaw himself didn’t know he had pancreatic cancer until Sunday, three days before it took his life.

It was a loss that could create problems for both the NFL and its players for a long time.

Despite his tendency to sound menacing, especially to those who criticized him, the man who headed the NFL Players Association for the last quarter-century was in his heart a dove, proud of the fact that under his watch there had been labor peace for more than two decades

“He was very tough but also a good listener. He never lost sight of the interests of the game and the big picture,” said former commissioner Paul Tagliabue, Upshaw’s close friend and his collaborator in ensuring the NFL has continued without a work stoppage longer than any other major North American sports league.

Soon after news of Upshaw’s death became public, the union’s executive board made a quick move by appointing Richard Berthelsen, the NFLPA’s chief counsel and Upshaw’s top aide, to take his place on an interim basis. Kevin Mawae of the Tennessee Titans, the union’s president, said it won’t even begin to put together a committee to search for a new executive director until March 2009 or later.

That search could go anywhere, although history suggests a former player. The names most often mentioned are former Minnesota running back Robert Smith and two former union presidents: Trace Armstrong and Troy Vincent.

That almost surely means Berthelsen, who has been involved in NFLPA labor negotiations for 37 years, will spearhead the talks aimed at getting a new contract and avoiding a 2010 season without a salary cap. Upshaw had vowed all along if that happens, the cap will never come back, something that could make the NFL more like baseball, where rich teams (think Yankees, Red Sox and Mets) buy players at will, while poorer ones endure one losing season after another (think Pirates, Royals and Nationals).

Berthelsen, of course, wasn’t even thinking about that Thursday. A close friend of Upshaw’s, he spent the day grieving, his telephone mailbox full with condolence wishes or calls from stunned players. Even Doug Allen, the union’s former assistant executive director, had trouble getting through to him.

“We’ve been playing phone tag all day,” Allen said just as his phone rang – finally – with a return call from Berthelsen.

In fact, Berthelsen has been partly responsible for many of the union’s gains over the last two decades, most often behind the scenes. The one thing he lacks is what made Upshaw such a draw to the union members: the fact Upshaw played and played well. A guard who spent his entire career with the Raiders, Upshaw was inducted into the Pro Football Hall of Fame in 1987, his first year of eligibility and, coincidentally, the year he led the last labor stoppage in the NFL.

“From what I hear, he was a pretty good player.” said Brandon Moore, the Jets’ player representative, who was 2 years old when Upshaw retired.

But Berthelsen’s legal skills will also be important.

Along with Jim Quinn and Jeffrey Kessler, the union’s outside counsels, he helped devise the legal strategy that in the long run got the NFLPA what it wanted after the 1987 strike: free agency.

Upshaw, in what the NFL viewed as typical bargaining rhetoric, had already announced the union would play it tough if it couldn’t reach agreement on a new deal by March 2010, the deadline preceding the capless year. Berthelsen, with Kessler still on board, is likely to do the same.

But that’s for later.

Right now both sides grieve for Upshaw and try to recover from the shock that O’Hara went through when he reported for work.