Sterling, Foden and a Champions League pointer: Five things we learnt from Watford 0 Manchester City 4

City were breathtaking in their victory at Vicarage Road

Manchester City's Raheem Sterling (r) celebrates scoring their first goal against Watford at Vicarage Road. Reuters

Raheem Sterling celebrates the opening goal. AFP

Ben Foster saves Raheem Sterling's penalty, only for the City star to score from the rebound. AFP

Raheem Sterling scores their second goal. Reuters

Manchester City's Raheem Sterling, right, celebrates with teammates after scoring his side's second goal. AP

Manchester City's Phil Foden, left, celebrates with Manchester City's Joao Cancelo after scoring his side's third goal. AP

Manchester City's Aymeric Laporte, left, scores his side's fourth goal. AP

Aymeric Laporte, right, celebrates after scoring his side's fourth goal. AP

Manchester City's English midfielder Phil Foden controls the ball at Vicarage Road. AFP

Watford's owner Gino Pozzo during the match. AP

Watford's goalkeeper Ben Foster makes a save. AP

Watford's Troy Deeney in action. Reuters

Watford's Craig Dawson shakes hands with Troy Deeney after the match. Getty

Watford's interim manager Hayden Mullins, right, and Manchester City's Pep Guardiola. AP

Manchester City manager Pep Guardiola has an incredible record against Watford. PA

roy Deeney of Watford and City manager Pep Guardiola. EPA

Manchester City's Phil Foden and Watford's Danny Welbeck after the match. Reuters

Pep Guardiola was pleased to see Manchester City take a step towards their best form with a 4-0 win over Watford ahead of next month's Champions League tie with Real Madrid.

A first-half brace from Raheem Sterling and goals after the break by Phil Foden and Aymeric Laporte helped them return to winning ways after losing to Arsenal on Saturday in the FA Cup semi-finals.

The win leaves Watford deep in relegation trouble with one game left of the Premier League season.

Here's what we learnt from a one-sided contest at Vicarage Road.

Raheem Sterling's best season yet

The star of the show yet again, the England forward scored two more to take his tally for the season to 29, and nine goals in eight starts since Project Restart.

When he plays like this he, and City, are unstoppable. He taunts defenders, runs at speed and knows when to pass, creating space for others.

He was somewhat fortunate to find himself in so much space for the first goal, but his finish was calm and deadly accurate. You know when things are going your way when his penalty was saved by Ben Foster but he was first to the rebound and had an easy tap-in.

City for the Champions League

Manchester City have a 2-1 lead over Real Madrid going into the second leg of their Champions League last 16 tie on August 7. Overcome the champions of Spain at the Etihad, and play like this to the best of their considerable ability and it's difficult to see who could stop them.

Granted, a possible quarter-final against Juventus and semi-final up against Barcelona or Bayern Munich is not exactly a stroll in the park, but free-scoring City will not be afraid of anyone and Pep Guardiola will be desperate to lift the biggest club trophy of them all.

Phil Foden, ready made superstar

The City midfielder only turned 20 two months ago, yet is proving to be a formidable player already. He has made 36 appearances for in all competitions this season, and scored eight goals, his latest coming against hapless Watford. More importantly, he has looked more and more comfortable in a team of superstars as the season has progressed, once again looking a class apart at Vicarage Road.

It's impossible to overestimate the impact of David Silva as City over the last decade, and of course the Spanish genius will be missed when he moves on this summer. But Guardiola will take a great deal of comfort from the fact he has a young Englishman ready to step up and take his place already on the books.

Look out, Liverpool

After another breathtaking performance it's difficult to fathom how City have managed to lose nine Premier League games this season. including at Norwich City, Wolves and Southampton.

Even Pep has been puzzled, by his own admission. But one thing is certain, Liverpool - still an incredible 15 points clear with a game in hand - will not be allowed to run away with the title again next season.

Pep will have City hungry to close that gap. Managers always say there is only one thing harder than winning the title, and that's keeping it. Look out for a almighty tussle between the Premier League heavyweights in 2020-21 - with Chelsea and Manchester United also determined to have a say.

Sacking three managers not the answer for Watford

Watford became the first Premier League team to sack three managers in a season when Nigel Pearson departed on Sunday, but the change of management made little difference.

No blame can be placed on interim boss Hayden Mullins, who had less than 48 hours to prepare to face one of the best sides in Europe, but how can players expect to respond when they don't know who is in charge one week to the next?

City have tormented Watford over the last few seasons - the last three games reads Manchester City 18 Watford 0 - but clearly changing management is not the route to success. Maybe the owners of the club need to rethink their own strategy for next season, which is more than likely going to be in the Championship after relegation at the weekend.

Since the Hornets were promoted to the Premier League in 2015, they've lost all 11  meetings with the Blues. Perhaps relegation will provide at least one relief - not facing City next season.