Koeman’s future has been in serious doubt after Barca were beaten 3-0 by Benfica in the Champions League on Wednesday, a defeat that leaves them bottom of the group.
Spanish media has been rife with reports that Barcelona president Joan Laporta is close to making a coaching change after Wednesday’s 3-0 loss at Benfica, the team's second loss in as many Champions League games this season.
Barcelona are in last place of Group E and at risk of not making the knockout rounds for the first time in 20 years.
Ronaldo's future had been in doubt after a difficult campaign during which Juventus lost their Serie A crown after nine years, exited the Champions League in the last 16 and only sealed fourth place and elite European football on the final day.
Gattuso was appointed as Fiorentina boss on 25 May less than 48 hours after announcing his departure from Napoli and had not been expected to start work until 1 July.
Allegri led Juve to four consecutive league and cup doubles with Italian Cup triumphs in 2015, 2016, 2017 and 2018. They finished below champions Inter Milan, AC Milan and Atalanta this season.
Juventus finished fourth in the Serie A standings having nearly missed out on Champions league spots.
Pirlo does not believe that the upcoming game against Bologna will be Ronaldo's final one with the club if they fail to qualify for elite European football.
Juve's European hopes depend on beaten cup finalists Atalanta's match against AC Milan in Bergamo, and Napoli's game at home against midtable Hellas Verona.
The dethroned league champions beat Atalanta 2-1 to win the Italian Cup for the 14th time after winning the Super Cup in January.
Just three points separate second-placed Atalanta and Juventus in fifth with two games left to play.
Serie A: AC Milan secure thumping win to leave Juventus out of top four; Atalanta back in second place
Milan move up to third, equal on 72 points with second-placed Atalanta, with Napoli a further two points behind in fourth and the final Champions League berth.
Juve's win moves them up to third as they target a Champions League spot, but are equal on 69 points with second-placed Atalanta and AC Milan in fourth.
Inter Milan are set to deny Juve a 10th consecutive crown with the Turin giants now battling for a Champions League spot.
Serie A: Matteo Darmian pushes Inter Milan to brink of A title with 'nine point' win, Atalanta move second
Inter are 11 points ahead of Atalanta, who moved second with a 5-0 rout of 10-man Bologna, with five games remaining.
Juventus president Andrea Agnelli was among the leaders of the 12-team Super League which collapsed in 48 hours amid pressure from fans and politicians.
Serie A: Juventus' Champions League qualification at risk, Inter Milan edge towards title despite Napoli draw
Leaders Inter Milan edged towards the Serie A title despite a 1-1 draw at Napoli, to pull 13 points ahead of Juventus who dropped to fourth place.
Coach Andrea Pirlo said Ronaldo, the top scorer in Serie A this season with 25 goals, would rest to avoid risking a more serious injury.
Serie A: Juventus drop Paulo Dybala, Weston McKennie and Arthur Melo from Turin derby for breaking COVID-19 protocols
The dropped trio were reported to have been fined by police who were called by neighbours to the lockdown get-together at US midfielder McKennie's Turin home on Wednesday night.
‘True champions never break’: Cristiano Ronaldo urges Juventus to move on from Champions League exit
The Juventus star spoke for the first time since the Serie A champions crashed out of the UEFA Champions League after a Round of 16 loss to Porto