Lovren and Manquillo contributed to a hugely impressive Liverpool display at Anfield, as Rodgers' team rounded off their pre-season preparations with a comprehensive 4-0 win over Bundesliga giants Dortmund.
Croatia international Lovren - signed from Southampton for a reported fee of £20 million last month - enjoyed a debut to remember by scoring Liverpool's second goal with a towering 14th-minute header.
And the 20-year-old Manquillo, who only joined on loan from Atletico Madrid last week, looked assured at right-back before being substituted to a standing ovation late on.
The vibrant displays of Liverpool's new-look front three of Daniel Sturridge, Raheem Sterling and, in particular, Philippe Coutinho are sure to attract the headlines as they showed life goes on at Anfield after the departure of Luis Suarez.
However, Rodgers was effusive in his praise of both his new defensive recruits after the game, which also included goals from Sturridge, Coutinho and Jordan Henderson.
"Dejan was perfect - he's what I've been looking for since Jamie Carragher left," said the Northern Irishman.
"He's a dominant centre-half who goes and attacks the ball and reads the game incredibly well.
"[We also saw] his quality with the pass. Both sides, left foot, right foot.
"As we found out last year [Lovren scored the winner for Southampton at Anfield in September 2013], he's dominant in both boxes with the way he attacks it.
"And young Javi Manquillo was outstanding.
"He's the type of full-back I like - he gets tight to people, can stop crosses but also has the energy to go and attack and get forward.
"I thought he was very, very good."
Lovren and Manquillo represent two of Rodgers' seven signings of a busy close-season.
But while the former Swansea City boss is satisfied with the strength of his squad, he is still eyeing more arrivals before the end of the transfer window.
"Hopefully there are another one or two to come in," he added.
One player who has been linked with a move away from Anfield in the wake of Lovren's arrival is Daniel Agger, who did not feature against Dortmund.
However, Rodgers denied rumours that his vice-captain is set for the exit door.
The Liverpool boss added: "I've read some stories, but we've had no enquiries about Dan.
"He's still getting work done on his knee - we haven't had any offers."
