PHOENIX -- Total focus on the task at hand is one reason Randy Johnson has fashioned a Hall of Fame career, and the big left-hander is counting on it to get him through this season. Johnson, who found out exactly one week ago Tuesday that he had a reherniation of a disc in his back, will take the mound on Thursday in the series finale against the Dodgers. How many starts he will make after that and how he will feel physically are all questions best left for another day. "I'm prepared to pitch Thursday and will do everything in my power to continue to go out there and pitch as effectively as I can and stay in the rotation," Johnson said. "More importantly, I don't know how much longer I can pitch with it. So I'm going to go into it with a positive frame of mind. I'll go as hard as I can as long as I can."
With Johnson pitching on Thursday, Livan Hernandez and the rest of the starters will be pushed back one day. Johnson threw 41 pitches during a simulated game on Monday, and based on how he recovered, the decision to start him was not a difficult one for Arizona manager Bob Melvin. "I said, 'How are you doing?' He said, 'Fine,' and I said, 'All right, Thursday,'" Melvin said. "That's basically how it went down." Johnson threw 113 pitches in his last start, a 5-1 win over Boston on June 10, but he is unlikely to throw more than 80-85 on Thursday. He was scheduled to start on June 16 in Baltimore, but pain in his back during his between-start throwing session was so severe, he was having trouble putting weight on his right leg when throwing. Johnson was placed on the disabled list and has missed a total of two starts. Back specialist Dr. Robert Watkins said that while he has a reherniation of the disc, he would be OK to prepare for his next start following some rest, a shot and some medication. No stranger to pitching with pain, Johnson made 33 starts with a similar back condition last year. He was asked on Tuesday if he might need to have surgery again on the back. "I prefer not to, obviously," he said. "I've only made nine starts coming off my last surgery, and I have probably 18 more. So let's just get through the Dodgers start and not look too far down the road. That's what I'm preparing myself for right now, and then I'll deal with whatever happens after that and so on and so on. Those are questions that I have, and there are no answers, so let's just wait until we cross that bridge." Speaking of Randys: Left-hander Randy Choate had his contracted selected from Triple-A Tucson on Tuesday to replace right-hander Jailen Peguero, who was optioned to Tucson. Choate appeared in 30 games for the D-backs last season, going 0-1 with a 3.94 ERA. He went to Spring Training this year with the Twins, but he opted out of his deal with a week left in camp because it appeared he would not make the team. After two weeks of not pitching, the D-backs signed him to a Minor League deal, and he drove 30 hours from Tampa to Tucson and was pitching the next day. "I had a pretty rough April," he said. "I didn't pitch the last week of Spring Training and the first week of the season. [It] took me a little bit to get back into my rhythm. Finally, about the beginning of May, I kind of hit my stride again and felt good on the mound." A 2.81 ERA in 28 games for Tucson earned his promotion. He and Doug Slaten give the D-backs two lefties in the bullpen for the first time this year. That's helpful, particularly against the Dodgers, who feature a host of dangerous left-handed hitters. "Randy's improved his game to where he's getting right-handers out, too," Melvin said. "He pitched two innings last night, so we feel like either of them can get through that one right-handed hitter. Probably Slaten is a little more apt to give us length, where we'd probably match up a little more with Choate -- just depends on how the game plays out." As for Peguero: Peguero pitched well initially after being called up earlier this month, but he struggled of late. "He's done some good things for us," Melvin said. "Pitched in the seventh inning once and got some big outs for us. [He] hadn't pitched as much recently, and his last two haven't been his best outings, but it's not like we needed to demote him because he was struggling significantly. We just needed to switch it up a little bit." Up next: The D-backs continue the four-game series with the Dodgers on Wednesday night with sinkerballers Brandon Webb and Derek Lowe locking horns in a 6:40 MST contest at Chase Field.
Steve Gilbert is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.