Three things we learned from the Community Shield

Narrow margins

When Kyle Walker leapt acrobatically into the air to hook Mohamed Salah's header off the goalline in the final seconds, it was a vivid demonstration of the narrow margins that are sure to settle the battle for supremacy between Manchester City and Liverpool this season.

"I'm a defender. I stop goals," Walker said. "It starts off the season. We can start our momentum, and hopefully we can replicate what we did last season."

Walker's incredible clearance, which allowed Pep Guardiola's team to eventually win on penalties, was reminiscent of City team-mate John Stones' remarkable stretch to block his clearance from deflecting into his own net against Liverpool last season.

Stones managed to stop 11 millimetres of the ball from crossing the line, setting the stage for a 2-1 City win that played a key role in their successful title defence as they held off Liverpool by one point.

That title race was only concluded on the last day of the season and required City to reel off a blistering sequence of victories to stop Liverpool, beaten just once all season in the league, winning their first English title since 1990.

With little to separate treble winners City and European champions Liverpool in Sunday's ferociously-fought 'friendly', the expected battle for the Premier League title between the rivals is likely to go down to the wire once more.

Sterling, Salah shake off rust

Raheem Sterling and Mohamed Salah were two of the driving forces behind Manchester City and Liverpool's success last season and they look set to lead the way again after the star forwards were at the heart of the best moments at Wembley.

Sterling always shines at Wembley for club and country and the England winger, who started up front before moving to the flanks after Leroy Sane's injury, was a constant menace with his pace and movement.

He opened the scoring with a close-range finish in the 12th minute, but showed a brief sign of rust when he wasted a chance to put the game out of Liverpool's reach in the second half as he stumbled when clean through on goal.

It is likely to be a rare slip from Sterling and the same will surely be said of Egypt's Salah.

While some might be concerned Salah failed to hit the target from a host of opportunities, he was by far Liverpool's most dangerous forward and on another day he would have had a hat-trick.

Schedule stress

Manchester City manager Pep Guardiola and Liverpool boss Jurgen Klopp are united in their belief that football's schedule makers are putting their players at risk with their unrelenting fixture list.

Liverpool were without Senegal winger Sadio Mane as he rested after the Africa Cup of Nations, while Manchester City didn't have Algeria's Riyad Mahrez following the same tournament.

Several other City and Liverpool stars including Mohamed Salah and Sergio Aguero have only recently returned to training after their international commitments in what is dubiously called the 'close-season'.

In the circumstances, both teams deserve credit for producing tenacious performances after so little time to recover.

But with the Premier League starting next Friday -- earlier than any of the other major leagues -- when Liverpool host Norwich, Klopp once again made it clear he believes the authorities are being unfair on the players by having such a small break before the domestic season begins.

And Guardiola, whose team open their league season at West Ham on Saturday, totally agreed, slamming a "crazy" schedule he hopes won't detrimentally affect City's title defence.