Kieschnick got to Chicago early Thursday morning and when he reported to Wrigley Field, he found his name in the starting lineup.
"I think he got in about 5:30 this morning, got a couple of hours of sleep," D-backs manager Kirk Gibson said with a smile. "But I don't think he'll be too tired."
Kieschnick was claimed off waivers from the Giants by the D-backs on April 4.
With Trumbo out, A.J. Pollock limited by a neck injury and Cody Ross not yet ready to play every day, Kieschnick could see some significant playing time.
"Just thought that he's a left-handed above average outfielder, got some pop and we'll be losing some of the pop with Trumbo being gone," Gibson said when asked why it was Kieschnick they called up. [We] considered some other guys and this is the guy that, as an organization, we thought would fit us best."
Kieschnick, who was hitting .281 in 18 games with Reno, got the news of his promotion Wednesday, which was an off-day for the Aces.
"I had just got done getting some groceries at the grocery store, so pretty much had to throw all that away," he said adding that it was a small price to pay to get back to the big leagues.
Kieschnick, who can play left and right field, made his Major League debut with the Giants last year. He appeared in 38 games for San Francisco and hit .202.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.