One player debuted in the big leagues as a Minnesota Twin on August 27.
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Chip Hale (2B/3B) – August 27, 1989 – Drafted by the Minnesota Twins in the 17th round of the 1987 amateur draft. Debuted in the Dome in a Twins 8-5 win over the Seattle Mariners going 1 for 5 with a run scored.
You can check out other Major League Debuts as Twins that I have done by going here.