Lollar was traded to the Padres near the end of spring training 1981, along with three other players, for outfielder Jerry Mumphrey and pitcher John Pacella.

He was in turn rewarded by being made the Padres' Opening Day starter in 1983, but he slumped badly, posting a record of 7–12 with an ERA of 4.61.

After the season, he was traded to the White Sox, along with Ozzie Guillén, Bill Long and Luis Salazar, primarily in exchange for LaMarr Hoyt.

While his 1986 season with the eventual American League champion Red Sox was forgettable, Lollar was undefeated, going 2–0.

Lollar played that season in the minors, posting a record of 3–4 with an ERA of 5.87 while splitting the year between the Detroit Tigers and St. Louis Cardinals organizations.

Lollar was considered a particularly good hitter for a pitcher, being asked to occasionally pinch-hit, and hitting eight career home runs in four seasons in the National League.

Despite not having batted in a major league game in nearly a year, Lollar singled off Kansas City Royals closer Dan Quisenberry.