Former Negeri Sembilan menteri besar Mohd Isa Abdul Samad said he was worried about several seats in the state in the last general election, but he did not expect Pakatan Harapan to capture the state.

"Even though I did not think (BN) would lose, we were definitely worried.

"We were worried when they put several candidates, whom we had predicted would not win - that is what worried us," he told Malaysiakini in an interview at his house in Port Dickson, which has been turned into the operations room for his campaign.

Mohd Isa, who was the state's menteri besar for 22 years, pointed out that some of the seats BN won in the 13th general election were slim-majority victories, which was already a cause of concern.

His worries were only exacerbated, he said, because the party leadership placed the "wrong candidates" in certain areas.

Negeri Sembilan fell to Pakatan Harapan for the first time in the last general election after the coalition won 20 out of the 36 state seats.

If Umno plans to recapture Negeri Sembilan, Isa said, the party's leadership and elected representatives would have to work hard.

"If their performance is good, and the leadership at the state and federal levels are accepted well, not only by the party members but also by the rakyat, then they might be able to regain (the state).

"But seeing the situation now, if we do not provide good service, it would not be easy to get the state back," he said.

However, Isa stopped short of providing specific ideas on how Umno could regain the confidence of the people.

"I am no longer an Umno member. Everyone was fighting to get (party positions) and now that they have it. Let them think about how they want to do it," he quipped.

Isa quit Umno in order to run in the Port Dickson by-election as an independent candidate, after Umno announced at this would boycott the polls.

The Port Dickson by-election was triggered when its incumbent MP Danyal Balagopal Abdullah vacated the seat to make way for PKR president-elect Anwar Ibrahim's return to Parliament.

Besides Anwar, the seven-cornered fight on Oct 13 will see Isa go up against PAS candidate Mohd Nazri Mokhtar, Anwar's former personal aide Mohd Saiful Bukhari Azlan, Stevie Chan, Lau Seck Yan and Kan Chee Yuen.