From "30th anniversary: Bob Welch does it all" by Chris Jaffe at The Hardball Times:
Thirty years ago today, Bob Welch had about as good a day as a pitcher could possibly have. He damn near won a game all by himself on the mound and at the plate.
On June 17, 1983, Welch took the hill for the Dodgers in Los Angeles against the visiting Cincinnati Reds. Normally, you’d expect it to be an easy win for the Dodgers, as they clearly were the superior team. The day began with LA sporting a 41-20 record, a full 15 games better than Cincinnati. However, the Reds had a nice leveling factor. Their ace pitcher, Mario Soto, was on the mound. An All-Star the previous year—and would be again this year—Soto’s ERA was barely over 2.00. While Welch was a nice pitcher, he was no Soto.