That's just what he came to Tempe to do.
The graduate student transfer from Penn State scored 18 of his 26 points in the second half and Arizona State pulled away to beat Washington State 66-47 on Sunday.
Jahii Carson added 14 points and Shaquielle McKissic 12 for the Sun Devils (12-3, 1-1 Pac-12), who were coming off a 76-65 home loss to Washington in their conference opener.
Marshall was 2 of 11 for four points against the Huskies on Thursday, then 9 of 14, including 4 of 7 3-pointers, on Sunday.
"It was great, what I work hard for," he said. "Coach does a great job of keeping us after practice and getting up shots. It just shows that hard work pays off."
DaVonte Lacy, a Curtis High School product, was back in the lineup eight days after an emergency appendectomy but left with 6:23 to go in the first half and did not return.
"We need him on the court and he's a big piece of what we do, especially on the offensive end," Cougars coach Ken Bone said, "and we are paying the price."
Freshman Que Johnson scored 18 for Washington State, which scored 68 points combined in their two games in the desert.
The Cougars (7-7, 0-2) shot 34 percent three days after their worst offensive showing in 76 years in a 60-25 loss to top-ranked Arizona Thursday night.
Just after drawing his third foul, Marshall scored 16 including three 3-pointers in an 18-3 run that finally opened the game up for the Sun Devils, 51-33, with 10:55 to play. Arizona State led by as many as 23 after that.
Before that, the Cougars made it close.
Arizona State used a 13-3 run to go up 23-12 on Carson's driving bank shot with five minutes left in the first half.
But the Cougars scored nine in a row to cut it to 25-23 on two free throws by Dexter Kernich-Drew 34.6 seconds before the break. McKissic's tip-in just before the buzzer put the Sun Devils ahead 27-23 at the break.
Barely two minutes into the second half, Carson's 3-pointer put Arizona State up 33-25, but Johnson sank consecutive 3s for the Cougars to slice it to 33-31 with 17:09 to play.
Marshall scored the game's next eight points with a three-point play, a drive to the basket and a 3-pointer, putting Arizona State up 41-31 with 14:03 to go.
His 26 were his most at Arizona State and three shy of his career high set for Penn State against Michigan State last Jan. 16.
"Jermaine, throughout his career, has demonstrated the ability to score," Sun Devils coach Herb Sendek said. "He finds ways to get buckets. When he's doing that, without showing off the obvious here, we're a lot better."
Sendek said the entire Arizona State team took better shots than it had in the disappointing loss to Washington.
"To take worse shots might not have been possible, though, than we took on Thursday night," he said. "We took shots on Thursday night that a bold person wouldn't take in a game of horse. ... I've seen some great horse games at family picnics through the years, trick shots, shots under the influence, and they wouldn't even rival some of the shots that our team took Thursday night."
Johnson, who made 7 of 10 shots, was the only Cougar player in double figures.
"I thought or defense was doing a good job, a really good job," Bone said. "We have got to get better offensively. It's hard when arguably your best player, definitely your best scorer, is not out there, so again to try to manufacture points in creative ways. It makes it a little bit difficult, to say the least, but you got to keep plugging at it."
Kernich-Drew, who missed the Arizona game with a concussion, also was back for Washington State. Lacy finished with four points and four rebounds in 11 minutes.
Washington State's 25-point struggle in Tucson was the Cougars' lowest-scoring game since they scored the same at Idaho in 1938. It also was the lowest-scoring game ever at McKale Center.