Pena ranks fourth in the National League with 14 holds. He sports a miniscule 0.69 ERA in 13 innings this month, as he has not given up a run since June 5, and right-handers are hitting .104 off him.
Lyon has been just as good, ranking second in the NL with 17 holds. He's 2-0 with a 1.17 ERA this month.
"They're very important to managers and teams and the success of the team," Melvin said of setup men in general. "They don't get the notoriety that the starters do and the closers do and probably never will to that extent, but I think that people are starting to realize how important those kind of guys are."
Unit may need relief:
A long Webb outing will also be important because five relievers combined to pitch six innings Tuesday without giving up a run until the 10th Tuesday, and Randy Johnson will likely throw around 85 pitches Thursday in his first game back off the disabled list (back injury).
Melvin said it would depend how Johnson feels after every inning and how hard he has to work in the outing.
"As far as pitch count goes, probably not what we've seen in the past," Melvin said. "We'll probably have to incrementally get into that. Now he's a pretty competitive guy. You can say this is going to be the number, and once he's out there pitching it could change a little bit, but we hope to get the results we've been getting before. It's just a little bit more of an unknown right now."
On the bright side:
Although Melvin admitted the Dodgers have had the D-backs number this season, with Los Angeles taking six of seven games entering Wednesday, he's well aware that the pitching matchups favor Arizona more so in the final two games than the first two.
D-backs ace Webb and No. 2 starter Johnson pitch Wednesday and Thursday, respectively, against Derek Lowe and Randy Wolf.
"You look at the pitching matchups at the beginning of the series as opposed to the end of the series, and obviously in theory they look a little better for us at the end," Melvin said. "They looked a little better for them at the beginning. You still have to play the game, and there's always a psychological effect of being beaten a few times leading into it, but any time Webbie's on the mound we feel good."
Big sticks on bench:
When Mark Reynolds tied Tuesday's game with a fourth-inning, pinch-hit homer, he extended Arizona's Major League lead with the club's ninth pinch-hit long ball of the season, five behind the franchise record of 14 in 2001. The Dodgers rank second in the Majors with six.
Tony Clark and Miguel Montero lead the D-backs with three homers off the bench apiece, two short of the individual record set by David Dellucci and Erubiel Durazo in 2001.
"I think it's a testament to the guys that we have preparing themselves prior to their at-bat to give themselves a chance to be successful," Clark said.
Melvin attributed it to players making themselves aware of the situation, led by the veteran Clark, who has hit eight pinch-hit homers for the D-backs the past three years. Clark said he offers any bit of advice he can to a group of youngsters who have never been in this situation before.
With the D-backs rotating Clark, Chad Tracy, Conor Jackson and Reynolds -- four hitters who possess power -- at the corner-infield spots and with Montero splitting time with Chris Snyder at catcher, Melvin has a bevy of power options in the clutch.
Outfielder Jeff DaVanon, rehabbing from offseason shoulder surgery, will likely be sent to advanced Class A Visalia Thursday, Melvin said. He won't be available before the All-Star break.
Jason Smith, who played two games for the D-backs before being placed on the disabled list (appendectomy), was in the Arizona clubhouse getting treatment for a pulled hamstring. He played three games at Visalia before going to Triple-A Tucson for eight, hitting .313 with two homers and six RBIs during the latter stop.
Army D-backs fans:
American Armed Forces serving overseas will be interviewed by D-backs announcers from the bottom of the fifth inning through the end of the game during FSN Arizona's "This One's For You" telecast against the Cardinals on July 4.
The American Forces Network will carry the telecast, and satellite feeds from Iraq and Afghanistan will allow FSN Arizona to interact with Arizona National Guard members who will be watching the game.
"This is our way of saying thanks to the great men and women in the United States military who serve our country so bravely in not only the Middle East, but around the world as well," said Mike Connelly, FSN Arizona's senior vice president and general manager, in a press release.
The D-backs finish their four-game series with the Dodgers on Thursday at 3:40 p.m. MST at Chase Field. Johnson will start against Wolf.