The phrase "lethal finisher" refers to someone who is very skillful at ending or completing a task or competition, often with great success or impact. Full definition
He has got to be the quickest and the most lethal finisher in Europe. (justarsenal.com)
Didier Drogba, considered by many to be one of the most lethal finishers in the Premier League, has been nothing more than a blip on the radar this season. (caughtoffside.com)
The player's lethal finishing ability and eye for goal has seen him touted as one of the greatest strikers in the world, and under Pep Guardiola, the player looks better than he's ever done. (caughtoffside.com)