Updated

NHL Commissioner Gary Bettman says there is not enough data yet to draw conclusions about the link between concussions and a degenerative brain ailment that has been found in four dead hockey players.

Player safety was a major topic Tuesday as the league wrapped up its two-day Board of Governors meeting in Pebble Beach, Calif.

It came a day after The New York Times reported that former New York Rangers enforcer Derek Boogaard suffered from chronic traumatic encephalopathy, an ailment related to Alzheimer's disease.

The 28-year-old Boogaard died in May of an accidental overdose of alcohol and oxycodone.

Former players Bob Probert, Reggie Fleming and Rick Martin previously were found to have CTE.