Arizona experiments with Jackson in left

Jackson starts in left field

PHOENIX -- The Conor Jackson left field experiment is back on.

After Jackson started at the position on Wednesday in New York, D-backs manager Bob Melvin gave him his second start of the season there in Friday night's game against the Royals at Chase Field.

With natural left fielder Eric Byrnes still on the disabled list with two hamstring tears, Melvin wants both Jackson and first baseman Chad Tracy in the lineup as much as possible.

Melvin was convinced by Jackson's defensive play on Wednesday, especially impressive due to the brutal nature of Shea Stadium.

"When he showed that he could do it, he did it in a tough place to play out there," Melvin said. "It's not like you're not getting some feedback from the fans out there in New York. If there was ever a dicey place to have to play a different position for the first time, he got the full brunt of it, and he did well."

Tracy also has experience in left field, but he just came off the disabled list for knee surgery and probably can't run as well as Jackson, who came up in the D-backs system as a left fielder before making the switch to first base in 2005.

"Conor's done it before," Melvin said. "I think he's a little bit more comfortable, especially in left field, and therefore it's him. I think he has a little more experience out there and to an extent, probably moves around a little better."

Melvin said Byrnes is "far better" than when he went on the disabled list but that there is still no timetable for his return.

Mike Ritter is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.