The left-hander pitched good enough Monday to lower his ERA to 1.57 in three minor league starts since leaving Extended Spring Training, where he was sidelined earlier this season with a sore shoulder.
Marshall pitched 6 1/3 innings Monday, yielding one run on three hits and striking out three while allowing one walk as Iowa (16-15) completed a four-game sweep of New Orleans with a 7-1 victory at Zephyr Field.
Marshall threw 87 pitches, 58 for strikes. He retired the first 10 batters he saw before allowing a one-out single in the third inning. The southpaw topped out at 89 mph according to teammate Carlos Marmol, who was responsible for charting pitch speeds with the radar gun.
In his first start for Iowa last Wednesday, Marshall said his focus was primarily on getting his curveball over for strikes. Coming into Monday's game, he shifted his attention toward better command of his fastball.
"I wanted to establish my fastball a little better today," Marshall said. "I kind of backed off it in the last start, but I felt it was a little better today. That's a really good thing for me because I can set up my pitches around that.
"I didn't throw as many curveballs today as I did in my last game, but it was still there when I needed it," Marshall added.
Marshall's only mistake came late in the game when Chip Ambres hit a solo home run that just missed a leaping Mike Kinkade's glove to skip over the left field wall in the seventh inning.
"He was able to get all of his pitches over," Iowa manager Buddy Bailey said of Marshall after the game. "His cutter has been real effective for him, and he has that natural tail on his fastball on the outer part of the plate. Then he has that down-and-in curveball.
"In Spring Training when he was trying to get healthy, his command wasn't very good and it was setting him back," Bailey noted. "Now that he's getting his command back and getting more innings, he's getting sharper and showing why he pitched in the big leagues last year."
Randy Wells pitched the final 2 2/3 innings to pick up his first save since 2005. Wells, who recently served a three-game suspension for plunking Nashville's Vinny Rottino with a pitch last week, allowed one hit (an infield single) and struck out four.
The right-hander began the year in the starting rotation, but was moved to the bullpen after allowing 16 runs in 13 innings.
"I don't know what it is or why, but for some reason, just coming in and not having to establish any one part of the plate is big for me," Wells said. "As bad as it is to say, I let the starters determine the way the game is going."
Iowa used a two-run homer to left-center by Micah Hoffpauir to jump out to an early 2-0 lead in the first inning. Hoffpauir connected on a 3-2 pitch from New Orleans starter Philip Humber for his fifth home run of the season.
The opposite field shot came after an 11-pitch at-bat.
"Patient, nothing. I was swinging at everything," Hoffpauir quipped. "I was just waiting to miss one, but luckily I didn't."
Hoffpauir was making his first start in nearly a week. He's been bothered by pain in his right shoulder after diving for a bunt two weeks ago.
"It hasn't had any real effect at all on my swing. The pain that I've had with it is when I extend my (glove) arm upward," Hoffpauir explained.
The Iowa offense totaled 12 hits Monday. The team entered the series batting just .248 as a whole, which placed second to last in the Pacific Coast League. They combined to tally 49 hits against New Orleans pitching.
"We had some really good timely hitting," Bailey said. "When you win four or five games in a row, it's a combination of a lot of things – hitting and pitching. Everybody has got to help out. Everybody on our roster performed in some way this series."
Cubs second base prospect Eric Patterson finished the series with nine hits in 18 at-bats to raise his average to .290 in 28 games. Scott Moore hit safely in all four games to raise his average to .241.
"It takes everybody to win a game the way it's played, and only one guy to lose it," Bailey said. "Fortunately, everybody had a good series."