An admirer of fire and brimstone battlers bristling with power and commitment, Lennon is under the blowtorch from fans of the Lancashire club that is languishing in the bottom three of the Championship – four points from safety.
And he made it clear Brattan - who joined The Trotters until 3 January immediately after signing a four-year deal with the Premier League leaders - is well short of the fitness levels required to play a part in the club's survival battle in the foreseeable future.
With Bolton's plight looking desperate and Lennon's job on the line, the former Celtic coach said after the 2-0 midweek defeat against Tommy Oar's Ipswich Town: “Luke just needs to work on his physicality – obviously his fitness levels are down compared to the rest.
“City contacted us and then we did some homework on him. It was an offer of a player to get some experience for him and to help City out.
“It’s good to have a relationship with Man City – I know some people there. He is training with us and had a run-out for the Under-21s on Monday.
"He got a run-out because he needs to get up to speed. Watching him in training, he can handle the ball."
It's been theorised that part of Bolton’s rationale in bringing Brattan after his hard-won release from Brisbane Roar to a dream move to the Etihad is to curry favour with City’s hierarchy in the light of Bolton's well-documented interest in snaring whiz-kid winger Brandon Barker on loan.
Barker, still just 18, signed a new five-year deal with City in August and is one of the club's brightest young prospects.
Accommodating the untried Brattan could significantly sweeten that potential deal.
"He will need to get accustomed to the pace of English football compared to the A-League," Lennon said of Brattan.
“It’s a big step even from the Under-21s to the Championship but you have to do it bit by bit.”
However, the likely lack of match minutes will not be what the 25-year-old needs at a time when he is seeking to cement a place in the Socceroos squad, having been part of the recent camp for the 2018 FIFA World Cup qualifier against Jordan.
"It is not costing the club a penny so it’s a no-brainer," Lennon said.
"He will work with the fitness coaches to get him near the level of the first-team boys and after that we will have a good look.
“We haven’t been able to bring a midfield player in at all since we have come in because we have had such a plethora of midfield players at the club.
“He is really the first we have brought in and it’s not a big expenditure or a big signing. It is just a player we would like to have a look at."
