One of Lersch's great baseball moments was a pitching victory in 1964's annual Midnight Sun Game.

He defeated the host Alaska Goldpanners of Fairbanks by a score of 10–5; 2,500 people were on hand to witness his win.

He made his MLB debut on April 8, 1969 when he surrendered a one-out two-run walk-off homer to Willie Smith in an eleven-inning Opening Day 7–6 loss to the Chicago Cubs at Wrigley Field.

He was credited with nine complete games, six saves and one shutout, a two-hitter against the Montreal Expos on September 30, 1972, at Jarry Park.

[2] He was traded along with Craig Robinson from the Phillies to the Braves for Ron Schueler at the Winter Meetings on December 3, 1973.