Clark, Bajcetic and Doak are all academy products of Liverpool and made their debuts for the Reds this year.
The Derby County EFL Cup third round game last month was the first Liverpool senior start for Clark and Bajcetic, while it was the debut match for Doak for the first team.
Lijnders praised Doak for learning quickly as well as possessing skills in the speed, mentality and technique department.
The assistant boss is happy with the development of Doak along with Clark and Bajcetic, describing their emergence as being like Liverpool signing three new players.
“He learns really quick”, Lijnders said about Doak in a press conference.
“Speed, mentality and technique – he has all three.
“We’re happy with three ‘new’ signings [Doak, Stefan Bajcetic and Bobby Clark], and I have to give credit to Matt Newbury, our academy scout, for bringing them to the club.”
Clark and Bajcetic have also made an appearance each in the Premier League, while Doak has played for three different age groups, the Under-18s, the Under-21s and the senior team.