NEW YORK -- Jose Canseco says injecting his teammates with steroids was "something so common" that he didn't give it much thought at the time.
"I injected them," Canseco tells Mike Wallace, according to a partial transcript of his upcoming interview with "60 Minutes" for a segment to be broadcast Sunday on CBS.
The interview was to be broadcast one day before the release of Canseco's book, "Juiced: Wild Times, Rampant 'Roids, Smash Hits & How Baseball Got Big."
ESPN's Pedro Gomez has seen a copy of Canseco's book, which includes this excerpt about the players' association's stance on drug testing: "I believe that plenty of people within the players' association must have known exactly which players were on steroids. And they did not care. If all you care about is hiking up players' salaries, why would you try to stop the steroid groundswell? Don't rock the boat. Think about it this way: If Don Fehr really believed that his players weren't doing steroids, wouldn't he have said, 'Okay, let a true drug testing program begin'? Nothing like the joke we had during the 2004 season, for example."
Canseco talks at length in the "60 Minutes" interview about using steroids with Mark McGwire while they were teammates on the Oakland A's. McGwire has firmly denied using the drugs.
"The first time injecting them in (McGwire's) buttocks," says Canseco, "it wasn't like you gave it a lot of thought. It was something so common."
Canseco wrote that he and McGwire injected steroids together "often" but told Wallace that he remembered injecting McGwire only a couple of times.
"Well, I think it was more inject ourselves," he said. "I think I injected him -- I mean, this is a long time ago -- once or twice for sure. I didn't keep track."
"I injected them. Absolutely," he said in the interview.
A few years ago, Canseco claimed that 80 percent of major-leaguers had taken steroids.
Canseco hit 462 home runs in a major-league career from 1985 to 2001.
Baseball recently adopted a tougher steroid-testing program after the sport came under increased scrutiny about the drugs.
Barry Bonds, Gary Sheffield and Jason Giambi testified before a federal grand jury investigating the Bay Area Laboratory Co-Operative known as BALCO.
Information from The Associated Press was used in this report.