The 23-year-old Lorenzen was called up from Triple-A Louisville to make his debut against the Milwaukee Brewers on Wednesday. He filled in for Homer Bailey, who is sidelined indefinitely by an injured ligament in his pitching elbow.
The Reds moved Bailey from the 15-day to the 60-day disabled list Wednesday. He hasn't yet decided whether to have surgery.
Parra and Tony Cingrani are the only left-handers in the Reds' bullpen other than closer Aroldis Chapman. Parra pitched last Thursday in Milwaukee, giving up a run in one inning. He is 0-1 with a 2.70 ERA in seven games.
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