Malen hits hat-trick as Roma rebound against declining Pisa
Roma, thrashed by runaway leaders Inter Milan in the last round, regained ground in the race for a top four place.
"We had a great reaction, and it wasn't easy because the second half in Milan was very disappointing," said Roma coach Gian Piero Gasperini.
His team moved level with Juventus, who are fifth, and one point behind Como in fourth. Como host Inter on Sunday. Juventus visit seventh place Atalanta on Saturday.
"We're still there, and now we should be rooting for Atalanta and Inter. We're giving it our all to reach the Champions League," said Gasperini.
Pisa remained anchored to the foot of the table.
Malen scored with all three of host Roma's shots on goals as he took his total to 10 in 12 Serie A appearances since joining on loan from Aston Villa in January.
In the third minute, two visiting players had a chance to intercept a Roma punt forward but Antonio Caracciolo could only knee the ball into Malen's pass.
The Dutch attacker sidestepped one more defender before firing home.
"Serie A matches are never easy, they become so if you break the deadlock after three minutes," said Gasperini.
Lorenzo Pellegrini hit the angle of post and bar with a free kick before helping set up Malen's second in the 43rd minute.
After Pisa repeatedly failed to clear, Devyne Rensch, who has yet to score in Serie A, picked up a loose ball in the box, played a one-two with Pellegrini and then poked a pass to Malen who rolled in from close range.
Malen completed his hat-trick after 51 minutes running onto a through pass from Matias Soule, turning away from two defenders and driving the ball home.
"He's incredibly valuable," said Gasperini of Malen.
"But if you play for Borussia Dortmund and in the Premier League as a young player, you're bound to have significant resources.
"The central striker role was the key to convincing him to come to Roma."