The clash broke out when some youth Akali workers objected to Bhagwant Mann allegedly criticising senior SAD leaders Harsimrat Kaur Badal and Bikram Singh Majithia, they said.
The fight continued for a few minutes during which the supporters of the rival parties hurled chairs at each other.
An Akali worker alleged that Bhagwant Mann was talking about Harsimrat and Majithia "in bad taste" and some of the workers raised objection over it. It was the AAP workers who clashed with the Akalis, he claimed.
The AAP workers later raised anti-Akali slogans and blocked the Malout-Delhi national highway to protest against the disruption of the rally. Stone-pelting was also reported at the Malout grain market.
"However, neither side has lodged any complaint so far," a police spokesperson said.
Meanwhile, condemning the disruption of the AAP rally at Malout, AAP's national spokesperson Jarnail Singh told reporters in Chandigarh that with the growing support of AAP among masses, opposition parties "have got frustrated and are adopting such tactics to create fear among AAP workers, who are courageous enough to give befitting reply to such tactics".