That "groove" is probably the path the piece of debris from the oil passage took when it locked up the engine. Is it in line with the oil hole in the crankshaft? If you're a gambling man, maybe you think that was the only piece of trash in there. Personally, I would disassemble everything and do a thorough cleanup of every oil gallery in the engine block and the crankshaft with rifle cleaning brushes. Good luck!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!