A hotly anticipated staging post in Manchester City's Pep Guardiola era arrives on Tuesday when Monaco visit the Etihad Stadium in the first leg of the Champions League last 16.

Guardiola was appointed to take City to the next level on the European stage and he has already masterminded a stirring 3-1 win over his former club Barcelona in the group phase.

But Monaco have been rampant this season, powering to the Ligue 1 summit with a tally of 76 goals that is unsurpassed in Europe's five major leagues, and Guardiola is keenly aware of the danger they pose.

"My impression against PSG and from what I've seen is they're a really strong team," he said recently of Leonardo Jardim's side, puffing out his cheeks for effect.

"They score a lot of goals, they are physical. We have to go to the gym in the next days!"

Guardiola and his assistant Mikel Arteta watched Monaco's game at Paris Saint-Germain last month, when a 92nd-minute equaliser from Bernardo Silva rescued a 1-1 draw.

Another Silva equaliser secured another 1-1 draw in Monaco's last outing, at Bastia on Friday, but in the main they have encountered scant resistance in the French top flight this season.

Monaco have averaged 2.92 goals per league game, scoring four or more on no fewer than 10 occasions, and have already prevailed on English soil, winning 2-1 at Tottenham Hotspur in the group stage.

Three successive wins have lifted City to second place in the Premier League table, eight points below leaders Chelsea, but they remain a work in progress.

It is just over a month since their scarring 4-0 defeat at Everton -- their fifth defeat of the campaign -- and Guardiola's selection decisions continue to raise eyebrows.

Claudio Bravo, signed amid great fanfare to replace Joe Hart, has been axed after a string of weak displays, meaning Willy Caballero, City's nominal third-choice goalkeeper in August, is now the number one.

What City's defensive configuration will be against Monaco, meanwhile, is anyone's guess.

A rotating cast of full-backs has seen midfielder Fernandinho fill in on both flanks of the defence of late, while Aleksandar Kolarov continues to flit between left-back and centre-back.

Yaya Toure has been successfully reintegrated into midfield alongside Kevin De Bruyne and David Silva, having previously been frozen out by Guardiola.

But the complicity that was developing between the front three of Raheem Sterling, Leroy Sane and Gabriel Jesus has been scuppered by the broken foot sustained by the latter.

Jesus's absence has allowed Sergio Aguero to reclaim his place up front.