The answer is as much as - and possibly more then - they could have expected.
Johnson tries to help the NL West-leading Diamondbacks avoid a fourth straight loss as they conclude a three-game series Wednesday against the San Diego Padres.
With ace Brandon Webb teaming with newcomer Dan Haren, the Diamondbacks (68-64) knew they would have a formidable top of the rotation this season. What they were unsure of was how much Johnson, who turns 45 on Sept. 10, could contribute coming off his second back surgery in less than a year.
Johnson went 4-3 with a 3.81 ERA in 10 starts in 2007, when his last appearance came on June 28 before back trouble ended his season.
This season didn’t start out well for the left-hander as he went 6-7 with a 5.23 ERA in his first 17 starts, but he was able to stay healthy.
Lately, though, Johnson (10-9, 4.03 ERA) has looked very much like the future Hall of Famer he is, going 6-2 with a 1.96 ERA over his last nine outings. He has walked seven and struck out 57 during that span.
Johnson struck out 13 - his highest total in four years - while limiting Florida to three runs - one earned - and five hits over seven innings, but was denied his 295th victory Friday in Arizona’s 5-4 loss. It was his 212th game with at least 10 strikeouts, ranking second all-time behind Nolan Ryan (215).
“He certainly pitched well enough to win,” Arizona manager Bob Melvin said. “He pitches quite a few games like that, where we don’t score a whole lot of runs. Seems like they’re always close games.”
Johnson has been outstanding in winning his last two starts against the Padres, allowing two runs and six hits in 12 1-3 innings while walking two and striking out 17. He is 15-5 with a 2.50 ERA in 25 career starts versus San Diego (50-82).
San Diego’s Brian Giles is 3-for-32 (.094) with a homer and 13 strikeouts against Johnson.
Webb struggled in his first attempt at becoming the majors’ first 20-game winner, giving up six runs in 4 2-3 innings as San Diego coasted to a 9-2 victory on Tuesday.
The loss was the third straight for the Diamondbacks, who nonetheless maintained a three-game lead over the struggling Los Angeles Dodgers in the West.
Giles and Kevin Kouzmanoff each drove in three runs, helping the Padres (50-82) win consecutive games for only the second time this month.
“I think he (Webb) probably didn’t have his best stuff,” Giles said. “But even when he doesn’t have his best stuff, he’s got quality stuff to get you out. We did a good job of waiting him out and getting balls that were up in the zone.”
Baek hopes to avoid losing four straight starts for the first time since during his 2004 rookie season with Seattle. The right-hander allowed all five runs in the fifth inning of Friday’s 5-0 loss at San Francisco, also giving up seven hits and two walks while striking out a career-high eight.
He is 1-1 with a 3.48 ERA in two starts this season against the Diamondbacks.