NEW YORK —Agent Scott Boras said Monday the number of major league teams rebuilding with younger, lower-cost rosters has become a cancer to the sport, attributing behavior to the strengthened luxury tax combining with restraints on draft-pick salaries.

Boras attributed baseball’s attendance drop to an increase in noncompetitive teams, predicted fans from perennial losers increasingly will stay away from ballparks until ticket prices are cut and said regional sports networks will negotiate lower rights fees with teams going into rebuild cycles.

Major league games averaged 30,042 fans last year, down 0.4 percent from 2016 and the lowest average since 2003.

J.D. Martinez, Mike Moustakas, Eric Hosmer and Jake Arrieta, all Boras clients, remain unsigned 10 days before spring training in a historically slow market. He said the luxury tax, envisioned by Commissioner Bud Selig to increase competitive balance, is having the opposite effect. He claimed incentives are needed to winning, such as increasing draft-pick money based on victories.

“They decided we’re going to have the 12 teams-a-tanking, if you will, and therefore you’ve got a noncompetitive cancer and this is completely opposite of what Commissioner Selig in good faith sought in bargaining,” Boras said.

Competitors watched a pair of successful rebuilds in the past two seasons. The Chicago Cubs won the 2016 World Series four years after losing 101 games and Houston took last year’s title four years after losing 111.

Since 2012, baseball’s collective bargaining agreement has limited the amount teams can spend on signing bonuses for amateur draft picks, making their cost predictable. Teams draft in reverse order of record, and clubs with higher selections are given larger amounts in their signing-bonus pools.

“There are a number of teams, let’s call it 10 or 12 in baseball, that are tearing down and rebuilding,” Seattle General Manager Jerry Dipoto said during the Mariners’ prespring training media availability Jan. 25. “You could argue that you’re going to compete with more clubs to try to get the first pick in the draft than you would to win the World Series.”

Agent Brodie Van Wagenen suggested Friday that players consider boycotting spring-training workouts, which start Feb. 14 but aren’t mandatory until Feb. 24. Dodgers closer Kenley Janson told Los Angeles reporters at the team’s FanFest on Jan. 27 that “maybe we have to go on strike, to be honest with you.”

Baseball has had labor peace since a 71/2-month strike that caused the cancellation of the 1994 World Series. Under the labor contract covering 2017-21, the highest luxury tax rate was raised from 50 percent to 95 percent and penalties were added that could push back a high-spending team’s top draft pick or cause a loss of selections.

RANGERS: Right-hander Bartolo Colon, 44, agreed to a minor-league contract and will attend big league spring training.

Colon would get a $1.75 million, one-year contract if added to the 40-man roster and could make an additional $1.3 million in performance bonuses based on innings.

Veteran infielder Darwin Barney signed a minor league contract that includes an invitation to major league spring training.

YANKEES: Marcus Thames was promoted to hitting coach, replacing Alan Cockrell on the staff of new manager Aaron Boone.

Thames spent the past two seasons as assistant coach under Cockrell, who served as assistant to Jeff Pentland in 2015 and replaced him after that season.

ASTROS: George Springer and Houston avoided salary arbitration by agreeing to a $24 million, two-year contract.

Springer gets $12 million annually and will be eligible for arbitration again after the 2019 season. The hearing had been scheduled for Tuesday.