PITTSBURGH » That retirement talk by James Harrison didn’t last nearly long enough for some NFL quarterbacks.

The three-time Pro Bowl linebacker resumed practicing yesterday with the Pittsburgh Steelers, a day after threatening to retire because of the NFL’s stricter enforcement of dangerous hits. Harrison was fined $75,000 Tuesday for a helmet hit on Browns wide receiver Mohamed Massaquoi.

On Wednesday, NFL commissioner Roger Goodell followed up the fines by releasing a memo emphasizing significant penalties will be imposed upon players who strike an opponent in the head or neck in violation of existing rules.

Harrison, arguing the restrictions won’t allow him to play football as he’s always played it, met with coach Mike Tomlin on Wednesday to discuss the changes. Tomlin decided to give Harrison a cooling-off day and sent him home.

Harrison, in his second season of a $51.2 million contract, issued this statement yesterday:

"I have come to the decision that I cannot and will not let the league office stop me from playing the game that I love," Harrison said.

"I will continue to play the game with the same passion, intensity and focus with which I have always played and let the chips fall where they may."

WR Jackson to report

Wide receiver Vincent Jackson will report to the San Diego Chargers next week and sign his contract tender, his agent said yesterday.

By reporting next Friday, Jackson will be able to serve a three-game, team-imposed suspension on the roster-exempt list, then play in the final six games to accrue his sixth season toward unrestricted free agency.