PHOENIX -- If it wasn't for the second deck at Chase Field, Brandon Allen's fifth-inning home run on Tuesday night might still be going.

"It was the farthest left-handed-hit home run I've seen here," right fielder Justin Upton said.

Upton was caught by cameras looking in amazement as the ball landed.

"Statistics say I hit a couple longer," Upton said. "I don't believe it."

Allen's homer carried an estimated 455 feet by ESPN Stats and Information.

"I guess it was a good shot," Allen said after Tuesday's loss. "I'll take it."

D-backs manager Kirk Gibson, who was known to hit a long home run or two back in his day, was as amazed as Upton with the home run.

"Oh, my gosh," he said. "How do they measure that?"

Putz nearing return from disabled list

PHOENIX -- D-backs closer J.J. Putz has only one more hurdle to clear before being activated from the disabled list.

"Personally, I'd like to see him pitch back-to-back [days]," D-backs manager Kirk Gibson said. "I want to make sure. I don't want him to be available one day in the closer's role and not the other."

Putz pitched an inning of scoreless relief on Tuesday night in extended spring training, threw 17 pitches, induced three ground-ball outs and reported no discomfort on Wednesday.

"It went well," Putz said. "Everything feels good. I still think I need maybe one more outing in a competitive atmosphere."

Gibson said on Wednesday that he expects Putz to head to Triple-A Reno and pitch Friday and Saturday before the team makes a decision on when to bring him back.

"It depends on when I go back-to-back days," Putz said. "I figure if I pitch Friday and don't pitch Saturday, it's kind of pointless for one game then a day off.

"It's good to get out there that second day and see how everything feels," he continued. "Not so much how you feel that day, but after those two days."

Putz has 21 saves with a 3.12 ERA in 34 games this season. He has been sidelined since July 1 with a right elbow injury.

"Realistically, probably the beginning of the next road trip," he said.

Worth noting

• D-backs manager Kirk Gibson said the team wouldn't make a decision on how to fill the fifth spot in the rotation until Sunday.

He said Barry Enright, who was optioned to Triple-A Reno on Wednesday, will stay on schedule and didn't rule out the possibility of the right-hander making a second consecutive start.

Left-hander Zach Duke, on the possibility that he could return to the rotation, said, "I'm open to anything. If I continue to throw well out of this role and it helps the team win, then that's what it's all about. It's about winning games at this point, and if that's the role I can best help the team, I'm all for it."