His instincts proved to be correct.
Madson allowed three runs in a season-high 7 2/3 innings and Philadelphia beat Arizona 7-3 for its fourth straight win.
"This team, I've noticed a lot that we really want to win on getaway day, so when we win the first two of a series, we usually sweep a team," Madson said. "So I felt (Tuesday) night after we won that we were going to win (Wednesday)."
Ryan Howard, Jimmy Rollins and Sal Fasano homered for Philadelphia, which improved to 8-1 on getaway day -- the last game of a road series. Madson (6-3) allowed eight hits in his third victory in four starts.
Fasano tied a career high with four hits and fell a triple shy of a cycle. He doubled in the second inning, singled in the fourth, homered in the sixth and singled in the eighth, raising his average 34 points to .281.
Fasano came into the series with one home run in 31 games. He hit two in a span of five at-bats Tuesday and Wednesday.
"Sometimes you get lucky," Fasano said. "You get a couple of bleeders to fall in for you and you hit a ball hard, so I'm pretty happy."
The Diamondbacks dropped their third in a row after returning from a 7-3 road trip capped by a four-game sweep of the Atlanta Braves. The Diamondbacks on Wednesday seemed stunned by the release of reliever Jason Grimsley, one day after federal agents searched his Scottsdale home as part of an investigation into steroid use by athletes. Grimsley's locker was empty when the home clubhouse was opened to the media Wednesday morning.
"For all of us, I think it was a bombshell," Arizona left fielder Luis Gonzalez said.
The Diamondbacks have been outscored 17-4 over the last two games. But Arizona shortstop Craig Counsell said the furor over Grimsley hasn't been a factor.
"Obviously, we've played poorly the last two days," Counsell said. "But when you go on the field, at least myself, I've got enough things to worry about."
Arizona's Dustin Nippert (0-1) made his first appearance of the season and allowed six earned runs and seven hits in five innings. He walked four and struck out three.
Nippert was on the bench at Triple-A Tucson on Tuesday night when he was told he would be starting Wednesday afternoon in Phoenix. He got in his car and made the 90-mile drive to Phoenix.
"I just packed my bags, ran up here and did the best I could," Nippert said. "It wasn't enough against this team that's pretty hot right now."
The Phillies jumped on Nippert early. With one out in the first, Chase Utley drew a walk and scored on Bobby Abreu's double.
Abreu helped spark another rally two innings later. After Abreu drew a two-out walk, Howard slammed a 438-foot home run into the center-field pavilion to give Philadelphia a 3-0 lead.
In the fourth, Nippert walked Abraham Nunez to lead off the inning. After Fasano singled and Madson bunted the runners over, Rollins hit a 382-foot shot into the right-field bleachers to put the Phils ahead 6-0.
Arizona made it 6-1 in the fifth on a single by Orlando Hudson. But the Phillies got the run back in the next inning on Fasano's homer to right field off reliever Enrique Gonzalez.
"They're a pretty good team," Nippert said. "They took care of business today."
Howard's homer was his 21st. That's third in the NL, behind Albert Pujols with 25 and Alfonso Soriano, who had 22 going into Wednesday's game. ... Gonzalez, recalled from Triple-A Tucson before the game, allowed one run in three innings. ... The Phils swept Arizona for the first time since May 7-9, 2004. ... Madson struck out three and did not issue a walk. ... It was the fourth career start for Nippert. ... The Diamondbacks turned their league-leading 77th double play of the season. ... Arizona RHP Jorge Julio has allowed one run in seven innings since his May 24 trade from the New York Mets, who open a four-game series at Arizona on Thursday night. ... Philadelphia's bullpen has a 1.01 ERA in its last 35 2-3 innings. ... The Phils are 14-4 when Howard homers.