Bob Feller had several similar All-Star appearances, including 1939 and 1946, but I went with 1941 as a representative performance.
I would classify 1941 as a typical Feller prime season. He led the league in strikeouts, innings, and walks, and complete games. By today's standards, his 6.8 SO/9 rate doesn't seem that special, but in that led the league as well. His ERA was down compared to previous seasons, but it was still a 125 OPS+.
The 1941 All-Star Game was held in Briggs Stadium (later to be known as Tiger Stadium) in Detroit. Just months later, the United States would enter World War II, and these games wouldn't really be the same until after the war.
This was Feller's first starting nod in four appearances, and like many of his other appearances, he pitched very well. In the first inning, he struck out two (Stan Hack, Pete Reiser). In the second, he struck out Bill Nicholson, and just missed giving up a home run to future HOFer Johnny Mize. Feller gave up his only hit of the contest to lead off the third, when Lonny Frey singled to right field, but Frey would be erased when he was caught stealing. Feller would end third and his outing with his fourth strikeout (Mel Ott).
Feller was removed in the bottom of the third for a pinch-hitter. If the DH was in play, Feller likely would have pitched at least another couple innings. In those days, not everyone on the roster played; several of the AL position players, for example, played the entire game. Feller left with the game a scoreless tie, but the action would pick up just after he left. The AL took a 1-0 lead in the fourth, but the NL came back with a run in the sixth and two runs each in the seventh and eighth innings. But the AL rallied for a run in the eighth, and Ted Williams' three-run homer in the bottom of the ninth gave the AL a dramatic walk-off 7-5 victory.