New York ? The NFL is going deeper into the wallets of players who get caught using steroids and other performance-enhancing drugs.

After four months of sometimes intense negotiations, the league and union announced Wednesday more extensive testing for performance-enhancing drugs and the addition of the blood-boosting substance EPO to its list of banned substances.

The union also agreed that players suspended after testing positive will, for the first time, forfeit a portion of their signing bonuses in addition to the salary they will lose during their time away. That is significant because the signing bonuses often are the only guaranteed portion of a player’s salary and can be larger than salaries, which sometimes are kept artificially low to keep the team under the salary cap.

“It is important that the NFL and its players continue to be leaders on the issue of illegal and dangerous performance-enhancing drugs in sports,” NFL commissioner Roger Goodell said. “These latest improvements will help ensure that we continue to have a strong and effective program. As we have done in the past, we will review and modify the policy on an ongoing basis.”

In addition to the new test for EPO, the agreement includes an increase from seven to 10 of the number of players on each team randomly tested each week during the season for steroids and other performance-enhancing drugs. That means there will be 12,000 tests each season, up from the current 10,000.

The new policy will make the NFL the only North American sports league to regularly test for EPO. Urine will be tested, not blood, for EPO. Baseball did a round of urine testing for EPO in 2005. Rob Manfred, MLB’s executive vice president for labor relations, said Wednesday there were no positives among the 500 samples tested.

Baseball conducts urine tests of major and minor league players for performance-enhancing drugs and stimulants, with each player tested at least twice randomly per year. Baseball does not conduct blood tests and does not test for EPO or human growth hormone. Baseball and its players union have agreed they will test for HGH if a urine test for that drug is validated.

A baseball player who tests positive for steroids is banned for 50 games for a first violation. A player who tests positive for stimulants is required to undergo counseling for a first violation and is subject to at least six additional tests over the next year.

The NBA randomly tests players four times a season. Players who test positive for steroids or performance-enhancing drugs get a 10-game suspension for a first offense, a 25-game ban for a second offense, a one-year suspension for a third offense and disqualification if they’re caught a fourth time.

In the NHL, every player is subject to up to two random tests a year. A first-time offender gets a 20-game suspension without pay and mandatory referral to the league’s substance abuse program. A second positive test carries a 60-game suspension.

The NFL policy mandates a four-game suspension for a first steroids offense and a year for a second.