New York ? Baseball commissioner Bud Selig asked players to agree to a 50-game suspension for first-time steroid offenders and a lifetime ban for a third violation under what he called a “three strikes and you are out approach” to doping.

In a letter sent this week to union head Donald Fehr, Selig proposed a 100-game ban for a second offense. He also asked the union to ban amphetamines, to have more frequent random tests and to appoint an independent person to administer the major-league drug-testing program.

“Third offenders should be banned permanently. I recognize the need for progressive discipline, but a third-time offender has no place in the game,” Selig wrote to Fehr. “Steroid users cheat the game. After three offenses, they have no place in it.”

Under the rules that began this season, a first offense gets a 10-day suspension, with the penalty increasing to 30 days for a second positive test, 60 days for a third and one year for a fourth. For a fifth positive, the penalty is at the commissioner’s discretion.

Baseball currently has no penalties for amphetamine use by players on 40-man major-league rosters. Amphetamines are banned for players under minor-league contracts.

“Last winter, we reopened our agreement to deal with steroids,” Selig wrote in the April 25 letter, a copy of which was obtained Saturday by the Associated Press. “I am asking you now to demonstrate once again to America that our relationship has improved to the point that we can act quickly and effectively deal with matters affecting the integrity of our great sport.”

Reached Saturday, Fehr said the union was not yet prepared to discuss Selig’s proposal.

“We’ll respond in due course,” Fehr said, adding he anticipated replying early next week.

Baseball players agreed during the offseason to reopen the drug agreement, which was not set to expire until December 2006. The new rules, which began in March, for the first time instituted suspensions for a first positive test for steroid use.

The new agreement, not scheduled to expire until December 2008, has been criticized by many in Congress as not tough enough.