MOCKED by his critics as "Sleepy Joe", 79-year-old Joseph Boakai has been sworn in as Liberia's oldest-ever president after scraping a win in November's run-off election, with the help of a former rebel commander.

It marks a generational shift, as Boakai takes the reins of power from the nation's youngest-ever elected leader, George Weah.

The former international football star rose to the presidency at the age of 51 after defeating Boakai in elections six years ago, but lost to him this time around by just over 20,000 votes.

For Rodney Sieh, the editor of Liberia's FrontPage Africa news site, Boakai's victory did not come as a surprise.

"People were fed up with the Weah administration - its corruption and opulence, the flashy cars and fancy restaurants. An official from the presidency even threw a bottle of Moet champagne over a flashy car he bought for his wife, and put a photo on social media.

"Voters questioned how officials could lead such lifestyles when ordinary people are struggling more and more to put food on the table, and to pay school fees for their children," he told the BBC.

Boakai won despite the fact that for years he has been derided by his opponents, and some ordinary Liberians on social media, after appearing to doze off at public meetings - a charge his aides deny, saying his small eyes and drooping eyelids give this impression.

To improve his image, Boakai often wore dark shades on the campaign trail this time around. But concerns remain about his fitness and health - especially as his term in office will end when he turns 85.

"Boakai did not travel a lot to the different counties to campaign for votes. He says he has a clean bill of health, but we know that he has a pacemaker because of a heart condition," Sieh said.

Before the election, Boakai dismissed the concerns about his health.

"Age should be a blessing to this country," he told the BBC.

He said he considered himself "a man who is old, who is wise, a man who is sound and a man who is committed to the cause of the country".

Boakai was vice-president in Nobel Peace Prize-winner Ellen Johnson Sirleaf's government until 2018, and contested the presidency under the banner of the United Party (UP).

Gyude Moore, a Senior Policy Fellow at the US-based Center for Global Development, said that what counted heavily in Boakai's favour was that voters saw him as a man they could trust after the scandals of the Weah administration.

"He has been involved in Liberian politics in some form or another for decades. He is regarded as an elder statesman," said Moore, who was a minister in the Sirleaf government and came to know Boakai well.

"I think he will be a competent manager, and I expect him to give ministerial posts to people who were deputy ministers and assistant ministers in our administration. So the government will have experience, which the Weah administration lacked," Moore told the BBC.

But the man to watch in the new government is Jeremiah Koung, who rose from being a street hawker to become a businessman and lawmaker - and is now set to be sworn in as vice-president at the age of 45.

"I think Boakai's selection of Koung as running-mate softened the debate [around his age], and made many Liberians move towards the Unity Party alliance," Liberia-based political analyst Daniel Sando told the BBC.

Moore described Koung as "young and energetic".

"He is bound to have presidential ambitions, and will demand a substantial role in government," Moore added.

Koung hails from the Movement for Reconstruction and Democracy (MRD) party, which is led by Prince Johnson - a pastor and lawmaker who was once a rebel commander.

His forces infamously captured the-then military ruler, Samuel Doe, in 1990, before killing him and slicing off his ears, while Johnson watched.

The murder was captured on an old-fashioned video tape, and copies of it were widely distributed by Johnson's men as they celebrated Doe's death.

Johnson claimed to have found God on that day, and went on to become a pastor, politician and lawmaker after peace was achieved in Liberia in 2003.

"Johnson is now a kingmaker in Liberian politics," Moore said, pointing out that he has strong support in Nimba, Liberia's second most-populous county, and the main battleground in elections.

"In the 2017 election, Prince Johnson endorsed Weah and that's why he won. But he backed Boakai in this election, saying Weah did not keep his promises.

"We don't yet know what promises Boakai made to him to get his endorsement, but his candidate has got the vice-presidency. Koung is popular among young people, especially in Nimba, and helps bridge the generational gap," Moore said.

Having forged an alliance with Johnson's party, Boakai is unlikely to yield to the demands of some civil society groups to establish a war crimes court.

"Families have suffered because of the war, and there will always be a demand for justice," Moore said.

"But Liberia got peace only after an undertaking that there will be no prosecutions. Peace has prevailed, and a whole generation has grown up in a democracy - unlike my generation, which lived through war."

Sieh said the new government's big challenge will be to tackle the country's economic crisis.