DENVER -- Edwin Jackson will return to the mound Monday night against the Diamondbacks following his worst Major League start.

On Wednesday night against the Padres, the Rays right-hander made his 12th start of the season and retired just one batter of the eight he faced in the first inning. Jackson allowed five hits, two walks and two home runs -- a three-run blast by Adrian Gonzalez and a two-run shot by Kevin Kouzmanoff -- to raise his ERA from 7.39 to 8.20 and put the Rays behind 5-0 before they ever hit.

Seeing Jackson have a short outing is something Rays fans have grown familiar with this season, but Jackson said the way it happened Wednesday night was different.

"That was one of the weird things," Jackson said. "That's one where I didn't have more balls than strikes, but I was out of the game quick. I went in the game like I'm going to make them put it in play. And they put it in play all right."

Even though the philosophy didn't work, Jackson will stick to the same plan.

"I'm sure the chances of that happening again, I mean it's possible, but I just don't see it every time you go out there and get them to put it in play you're going to have the same results," Jackson said.

Jackson knows he has not pitched well, but he said he needs to move on.

"You have to acknowledge the past, but you can't really harp on it," Jackson said. "You have to just find a way where you can get it out of your mind, at least the day you've got to pitch. When the time comes for the next start you can't have that anywhere on your mind. You think negative and negative things happen."

Jackson has worked with Rays pitching coach Jim Hickey between starts and they have tried not to overdo it.

"If you've got the guy thinking 'I'm supposed to be doing this, I'm supposed to be doing that,' it can almost have a worsening effect," Hickey said. "So we try to keep it simple. Take it to the least common denominator. And we've worked on a couple of things, but we've tried to keep it very basic."

Given Jackson's poor season, it's likely he's close to getting bumped from the rotation if his performance doesn't improve. Jason Hammel, who was recalled from Triple-A Durham last Monday, relieved Jackson Wednesday and allowed three runs in 6 2/3 innings. If Jackson is bumped, Hammel would be his likely replacement. But, Rays manager Joe Maddon hasn't given up on Jackson yet. Having the manager in his corner has meant a lot to Jackson.

"It definitely means a lot to me, because there are a lot of teams where I wouldn't be in the same situation," Jackson said. "So it definitely shows the confidence he has in me. Now it's up to me to go out and prove that it wasn't a mistake."

And while Jackson doesn't like to dwell on the past, this is one time he might want to look back in the Edwin Jackson archives. On his 20th birthday, Jackson pitched for the Dodgers against the Diamondbacks and Randy Johnson on Sept. 7, 2003 at Bank One Ballpark. He gave up one run on four hits and no walks in six innings to earn the win in a 4-1 Dodgers victory.

"At that point, I was dumbfounded, get the ball, go out there and throw," Jackson said. "Seems like the more you learn the more you get into your own head. When you're dumbfounded to the situation your natural ability just takes over."

Near cycle: Brendan Harris had the single, double and home run, but lacked a triple from getting the cycle when he took his last turn at the plate Saturday night.

Harris said he didn't spend too much time thinking about getting the cycle when he stepped into the batter's box for his final at-bat.

"You're always thinking, 'Hit something hard,'" Harris said. "But I did kind of look at the gaps to see if I would have a chance."

No player in Rays history has hit for the cycle. Harris said he turned the trick in high school and twice during Minor League games he had the double, triple, and home run before his fourth at-bat.

"But I couldn't get the single," he said.

Harris walked in his final at-bat Saturday night.

This and that: According to Maddon, B.J. Upton, who is on the 15-day disabled list with a left quadriceps strain, told Rays trainers: "I feel like I have a leg again." Maddon concluded the message indicated that his second baseman is close to returning. ... Rocco Baldelli (15-day DL with a left hamstring strain) was scheduled to be the designated hitter for Durham on Sunday and to play center field for the Bulls on Monday.

Up next: The Rays will begin a three-game series against the Diamondbacks on Monday in a 9:40 p.m. ET contest at Bank One Ballpark. Jackson will start for the Rays and will be opposed by right-hander Livan Hernandez.