Liam Neeson appeared on "SportsCenter" yesterday to talk football -- problem is, he doesn't know a damn thing about the sport ... and when he realized the interview was being aired live, he totally dropped an S-bomb.
Neeson is currenty on a hardcore promotional tour for his new movie "Taken 2" ... and someone thought it would be a good idea to let ESPN grill him about the NFL.
After the first question, a stumped Liam said, "Ok, we better start again -- can we? Are we live? Oh, sh*t."
When the anchor continued to press ... asking about Tim Tebow, the replacement refs and the 49ers ... Neeson responded, "See, you're speaking ancient Arabic to me buddy ... I swear to you ... I just don't understand the game."
For the record, Neeson -- who grew up in Ireland -- says he's a huge sports fan ... especially when it comes to boxing, basketball and hurling ... which was apparently an Olympic sport back in 1904.