The NBA has warned one of the world's best-loved basketball franchises, the Chicago Bulls, for resting healthy players in what appears to be an attempt to lose intentionally to boost their chances of a top draft pick, according to several reports on Tuesday.

Chicago, who have lost 42 of their 63 games thus far this season, had rested centre Robin Lopez and guard Justin Holiday in recent weeks but after a conversation with the league, agreed to play the two players more extensively.

The league discourages the practice of resting healthy players in an attempt to limit overt "tanking" by teams searching for a top pick in the NBA draft.

Dallas Mavericks owner Mark Cuban was fined $600,000 last month for comments he made on a podcast about losing being the best option for the team. The league reportedly sent word to all team owners clarifying its stance.

Chicago's Lopez is averaging 12.3 points and 4.7 rebounds per game this season. Meanwhile, the 28-year-old Holiday is averaging 13.0 points and 4.5 rebounds on the season.

The team sits 12th of 15 in the Eastern Conference, 12 games behind the Miami Heat, who occupy the eighth and final playoff berth.

The NBA already brought in a "draft lottery" system in 1985 that means the worst team is no longer guaranteed the best pick in the draft in an effort to prevent tanking but finishing low in the standings still stands to improve a team's chances of securing the best college talent.

Additional reporting by Reuters