Among those who may become active players once again are former Umno Youth chief Ahmad Zahid Hamidi and supreme council member Shahrir Samad.
Ahmad Zahid's political aspirations hit a brick wall when his mentor and ex-deputy premier Anwar Ibrahim was sacked from the government and party in 1998.
On the other hand, Shahrir impeded his ascent by pledging allegiance to Mahathir's former nemesis Tengku Razaleigh Hamzah when the latter unsuccessfully challenged the premier for control of Umno in 1987.
Apart from the duo, there are talks too that Razaleigh, Musa Hitam and Rais Yatim may make their presence felt once Mahathir steps down in October.
Musa, who was the premier's first deputy, and Rais had also aligned themselves with Razaleigh during the 1987 crisis.
Razaleigh and Rais later formed a splinter party called Semangat 46. The party disbanded after the 1995 general election and the duo returned to Umno with their members en masse.
Although, Abdullah himself had supported Razaleigh and his men, he however did not join their party but chose to remain in Umno with Mahathir instead.