LONDON - Line judges face an uncertain future after the ATP announced they will be replaced by "electronic line calls" at this year's inaugural Next Gen Finals in Milan.

For the first time at an ATP event, the chair umpire will be the only official on court, with 'Hawk-Eye Live' technology used to judge whether shots are in or out.

Decisions will be final, with players unable to challenge calls as they do at most tournaments via Hawk-Eye replays.