Top Amsterdam club Ajax on Saturday said it will appoint the relatively inexperienced as new head coach following the departure of Peter Bosz for Borussia Dortmund after a single season.
"He (Keizer) will shortly sign a contract starting 1 July 2017 with a span of two years," Ajax said in a statement.
"The agreement has an option for an added year," the Amsterdam football powerhouse said.
Keizer is currently head coach of Jong Ajax (Young Ajax), the powerful club's second team which shot to second place in this years' second tier Jupiler League behind VVV-Venlo.
Dutch media have called his appointment "a gamble" as Keizer lacked experience on the highest level, having only worked with small Dutch clubs such as Cambuur and Emmen and taking the field for Ajax only four times as a player.
But Ajax said it believed Keizer to be the right man for the job.
"Keizer was the most suitable candidate from the moment there was a possibility that we would be looking for a new coach," Ajax general manager and goalkeeping legend Edwin van der Sar said.
"He knows the players, the organisation and supports the club's philosophy," added Van der Sar, one of the most-capped Dutch national players who also took the field for Ajax, Juventus and Manchester United.
"We had some positive talks and I feel the organisation's confidence in me," Keizer said in the statement.
"It's a great opportunity I'd like to grab with both hands," he added.
"Currently I'm still on holiday but will soon proudly sign the new contract," he said.
Bosz was named Borussia Dortmund coach earlier this month.
German media reports say Dortmund agreed to pay Ajax five million euros ($5.6 million, £4.3 million) to bring in Bosz, with SID, an AFP subsidiary, saying the fee paid was "the highest in the history of the Bundesliga" for a coach.
Ajax lost the Europa League final to Manchester United last month, and at home, finished second to archrivals Feyenoord.