David Goffin wilted in the second set and the Swiss great took advantage, easing to his 102nd tour-level title ahead of his favourite Grand Slam.
Roger Federer outclassed David Goffin to claim a landmark 10th Halle Open title on Sunday.
Federer had never won a single tournament on more than nine occasions before sealing a 7-6 (7-2) 6-1 victory over the unseeded Belgian.
The 20-time grand slam champion was made to work in a tight first set in Germany, but dominated the second to claim an astonishing 102nd tour-level title as Goffin wilted.
Federer's serve was not firing on all cylinders in the opening set before he took complete command in his 13th Halle final just over a week before going in search of a ninth Wimbledon triumph.
The Swiss maestro said his game was where he wanted it to be after overcoming Pierre-Hugues Herbert at the semi-final stage, but Goffin forced the only break points of the first set.
Federer fended all three off in the fifth game to lead 3-2 and was impeccable in the breaker, drilling down a fifth ace following a majestic half-volley before Goffin was long with a return to go a set down.
The world number three swarmed all over his 33-ranked opponent in the second set, Goffin's serve getting him into trouble.
Goffin double-faulted five times in the second set and won just 56 per cent of points on his first serve, throwing down his racket after being broken in the first game.
A ruthless Federer won four games in a row to get his hands on the trophy yet again, victory sealed when a Goffin volley drifted wide.