The Arizona ace hopes that remains the case as he tries to become the major's first 16-game winner as the Diamondbacks continue their home series with the Pirates on Tuesday night.Webb (15-4, 3.04 ERA) looks for his fifth consecutive win after allowing a run and six hits while striking out six in eight innings of a 2-1 win over the Los Angeles Dodgers on Thursday."That was probably some of the best stuff I've had all year," said Webb, who was the first pitcher to 15 wins this season and is 4-0 with a 2.63 ERA in his last seven starts. "I was able to keep the ball down. I felt real sound."The right-hander has usually been at his best against Pittsburgh, owning a 4-0 record with a 2.41 ERA in five career starts versus the Pirates. He gave up a run in seven innings of a 3-1 victory at Pittsburgh on June 6.Arizona (58-54) avoided a third straight loss by beating Pittsburgh 13-7 in Monday's opener.Mark Reynolds had three hits including a homer and three RBIs, while Chris Young also had three hits to snap an 0-for-18 skid for the Diamondbacks, who have won 11 of 16 and own a 1 1/2-game lead over the Los Angeles Dodgers in the NL West."Guys are beginning to pick it up after the break," Reynolds said. "We know they're not going to hand us the division."Young might be hitting .234 on the season, but is 8-for-20 with three doubles and two triples against Pittsburgh (51-61) in 2008.Reynolds, meanwhile, is batting .306 (11-for-36) with three home runs and nine RBIs in his last nine games for Arizona, which recorded a season high for runs and hits (18) Monday. He is also 3-for-3 with two doubles and a homer against Pittsburgh's scheduled Tuesday starter Zach Duke.Duke (4-9, 5.27) looks to avoid a sixth straight loss Tuesday and is 0-5 with a 7.23 ERA in nine starts since allowing two runs in six innings to earn the victory in a 5-3 win over Arizona on June 9.The left-hander gave up six runs and eight hits in five innings of a 7-4 loss to Colorado on Wednesday."He's not hitting his spots as effectively," Pittsburgh manager John Russell said. "That's what's hurting him. When he's effective, he's staying down in the zone."Duke, who has an 11.25 ERA in three starts since the All-Star break, is 1-1 with a 5.29 ERA in three career starts against Arizona.Freddy Sanchez and Doug Mientkiewicz each had three hits with an RBI, while Mientkiewicz and Jason Michaels homered for Pittsburgh, which has lost three in a row while being outscored 26-13."We know we can score," Russell said. "We just let people score too many against us."All-Star Nate McLouth had two hits with an RBI on Monday, and is 4-for-8 with a double off Webb in his career.