New York Knicks guard J.R. Smith has been fined $50,000 by the NBA for what the league describes as "recurring instances of unsportsmanlike conduct."

The fine comes after Smith tried to untie the shoe of Detroit's Greg Monroe at the free throw lane on Tuesday.  The league had asked Smith to refrain from such behavior prior to that Tuesday contest after Smith was successful at untying Dallas' Shawn Marion's shoelaces on Sunday.

Smith reached out via Twitter on Wednesday to apologize.

Knicks head coach Mike Woodson said Smith's actions were unacceptable. "I'm not happy about this because he was warned, he comes back, and he makes the same mistake, and it's not right," Woodson said speaking on ESPN Radio. "It's just got to stop. I keep saying this every time something pops up, but it's got to stop."

Smith is no stranger to being in trouble with the league and this marks his second infraction with the NBA this season and has racked up over $100,000 in fines since joining the Knicks in 2011.