At the Kirkby training base, the players spent the first couple of days undergoing the usual individual tests before getting on the pitch with the ball on Thursday and Friday.
Iraola is heavily involved in these sessions and often says "bravo" when he sees something he likes. The intensity is evident to see, particularly in the training videos uploaded by Liverpool's official channels.
Iraola and his coaching staff spend most of their day at the training ground - with a major emphasis on assessing the capabilities of the current squad.
The new head coach has told players that he's viewing them as new signings. Harvey Elliott returned a week earlier than expected while Curtis Jones looks like "he has had a great summer", according to one source. Jeremy Jacquet, who has been given the number five shirt, is settling in nicely and has recovered from his shoulder injury.
On the whole, the players have returned in "good nick", with medical staff impressed. When it comes to endurance, under Jurgen Klopp the players would do a lactate test while it was a six-minute race test under Slot.
Iraola's fitness test is slightly different - players move on a pitch with diagonals and cones to replicate changes of direction with high intensity.
"It's deceptive as your legs just go," defender Joe Gomez can be heard saying to Jones.
Those at the training ground say there is certainly a youthful vibe to the squad, with eight players on World Cup duty yet to join. As one source puts it: "This really is a chance for a new group to emerge before more of the seniors return."
"Definitely there are going to be changes," Iraola told Stan Sports in an interview. "A lot of senior players, players who have won everything here have left and we need other players to not replace them but assume (more responsibility) in terms of inside and outside the pitch."
Coming into a club the size of Liverpool has certainly been different for Iraola but there is a general respect around the building for the 44-year-old and the job he did at Bournemouth.
If his first week is anything to go by, Iraola is confident and certainly comfortable but not necessarily box office. Perhaps one way to put it for now is that his presence won't be felt yet like it was with a big character like Klopp.
Those who know him well believe he won't change his ways and Iraola said as much in his introductory press conference.
Come Monday afternoon, Liverpool will be flying across the Atlantic to Chicago, where they will be based for their pre-season tour that also includes fixtures in Nashville and New York.
That trip will offer Iraola the first real chance of working with an expanded group of players, with most of the remaining first team squad expected to join up, and a range of academy players also travelling, including 15-year-old Josh Abe.
Either side of the three scheduled friendlies, where most will get playing time, double training sessions are scheduled in the heat. Both Iraola and his squad will know that from now on, the pressure will only heat up too.
