The pair have worked together extensively over the years, with Blackwell in the dugout alongside Warnock at Huddersfield, Plymouth, Bury, Sheffield United and Crystal Palace - as well as when the 66-year-old was formerly in charge of the R's.
Warnock was given the job as caretaker boss on November 4 after the sacking of Chris Ramsey, having previously been appointed as first-team advisor at the Sky Bet Championship side.
His first game in temporary charge saw Rangers draw 0-0 at home to Preston and, with games coming up against three of the current top-four sides in the division as well as hosting his former club Leeds, Warnock is pleased to have a familiar face helping him on the training ground.
"I know how Kevin works," he told QPR's official website
"He is very good on the training field and will provide me with an extra pair of eyes
I have spoken with Les (Ferdinand, director of football), and I have to operate as the head coach - for however long that might be
"When you look at the fixtures coming up, I don't think anyone will be rushing in to take over for those! We've got to embrace it and give it our best shot."
The club also paid their respects to former goalkeeper Tommaso Trani - who died aged 21 after a short illness.
The Italian featured for AC Milan's youth team before moving to QPR's academy and Warnock, who was in charge when Trani first joined the club in 2011, paid tribute to him.
"This is absolutely tragic news
Tommaso was such a lovely, lovely lad," he said
"When something terrible like this happens it opens everybody's eyes to the fact that football is only a game
There is nothing more important than your health
"It gives us all a sense of perspective, particularly as he was so young
My thoughts are with his family."
Source : PA
Source: PA