By the time, several girls from her local softball team had been
scouted and signed by the league; Janssen went to a tryout in 1946 but was not signed. At a second tryout in 1948, she was accepted and assigned to the
South Bend Blue Sox for a couple of days before being sent to the
Grand Rapids Chicks. Janssen had a 4–4 record with a 3.98
earned run average in 11 games and was released after one month of action. According to Janssen, she was released because she "couldn't throw a
curveball". In two of those games, Janssen was asked to switch to the Sallies and serve as playing
manager as well as
chaperone. She also led her Colleens team in pitching and had two one-hitter
shutouts against Springfield at ballparks in
Oklahoma and
South Carolina. Janssen finished the tour with a 16–6 record in 23 pitching appearances, which were not recorded in official statistics by the league due to the tour's nature as exhibition games.
1950: Peoria Redwings and Fort Wayne Daisies Janssen was promoted to the
Peoria Redwings in 1950 and pitched for the
Fort Wayne Daisies in the postseason. She went 3–3 with a 3.87 ERA in 19 games for Peoria and Fort Wayne, and pitched 12 innings of shutout ball without a decision in three playoff games as the Daisies lost to the
Rockford Peaches in the
best-of-seven final round.
1951: Fort Wayne, Peoira, Kalamazoo Lassies and Battle Creek Belles She opened the
1951 season with Fort Wayne and returned to Peoria early in the year. Janssen was then sent to the
Kalamazoo Lassies during the midseason and finished the year with the
Battle Creek Belles. Through the season, Janssen posted a career-best 26
games pitched, only six behind Belles teammate
Migdalia Pérez, while also setting career-highs in ERA (2.67),
innings pitched (145) and
strikeouts (43). Despite her performance, the team finished with a 6–10 losing record.
1952: Battle Creek Belles Janssen spent the entire
1952 season with Battle Creek and was used in
relief duties, a seldom used role in the league. She appeared in only five games, going 0–1 with a 5.00 ERA in 18 innings. == Post Baseball Career ==