More than two decades ago, a young man walked into Professor S Jayakumar's law class at the National University of Singapore and immediately caught the latter's eye.

"The very first tutorial on constitutional law which he attended I could tell he was an exceptionally bright student," said Prof Jayakumar, who was then the Dean of the law faculty.

And that name sprung to mind in 1981, when Prof Jayakumar himself a fresh face in politics at the time was asked by then-Deputy Prime Minister Goh Chok Tong to "try to get a few more lawyers" into politics.

"Shanmugam was one of the names I recommended," he said, in reference to the man who succeeded him as Law Minister at the start of this month.

Tasked to "sound out" Mr K Shanmugam, Prof Jayakumar who retains his post as Deputy Prime Minister invited him to his office and popped the question of whether he would consider joining politics.

"He almost fell off his chair," said Prof Jayakumar. "He said: 'Why me?' He was interested in law practice.

"I said: 'Look, that was the same response when I was asked.' I wanted to be a law professor for the rest of my life."

After taking time to consider, Mr Shanmugam threw his hat into the ring and was invited to an interview for potential election candidates.

He told the People's Action Party's bigwigs that his ambition in life "was to be one of the best lawyers in Singapore", Prof Jayakumar recalled.

"So now he has achieved that and I'm glad that he has taken on this bigger role," Prof Jayakumar said.

Mr Shanmugam was elected to Parliament in 1988 as part of the PAP team in Sembawang Group Representation Constituency.

But up until March 31 when the latest round of Cabinet appointments was announced the identity of Prof Jayakumar's successor was a subject of public speculation, with Prime Minister Lee Hsien Loong telling Parliament last year about the Law Minister's desire to step down and the difficulty in finding a worthy replacement.

Prof Jayakumar hinted that Mr Shanmugam had been on the radar for a while as his potential successor.

"You should ask the Prime Minister on the details of the to-ing and fro-ing but I just think the time was ripe now for Mr Shanmugam," he said.

The fact that Mr Shanmugam was at "the height of his legal career" meant that it "could not have been an easy decision" for anyone in his shoes, Prof Jayakumar pointed out.

"It could have been a more difficult position say, eight or nine years ago when he was still in the process of pursuing his career."

Smiling, Prof Jayakumar added: "But whatever the reasons, I am glad that he agreed otherwise, I would have to be there for many more years." - TODAY/ar