There may be no stopping the A-League's biggest clubs once more this season, but 2018-19 shapes as bringing several intriguing storylines across the competition.

Sydney FC – last season's premiers – and champions Melbourne Victory are again the favourites to claim trophies this campaign.

But there will be hope the rest can at least close the gap to the Sky Blues, who finished 14 points clear in the regular season in 2017-18.

While Victory and Sydney have added star power, Tony Popovic has arrived in Perth, Markus Babbel in western Sydney and the Central Coast Mariners have made plenty of waves in the pre-season thanks to Usain Bolt.

With Melbourne City eyeing a maiden A-League trophy and last season's grand finalists the Newcastle Jets settled, the 2018-19 A-League campaign brings plenty of potential.

Will Sydney and Victory continue their dominance?

Of the last eight A-League premierships and championships, six have been won by either Sydney or Victory. The Sky Blues are back-to-back premiers – along with a 2017 Grand Final win – and Victory have won two of the past four championships, to go with the 2014-15 premiership. However, there have been changes at both clubs, the most notable being Graham Arnold's departure from Sydney to take charge of Australia. But Siem de Jong has arrived on loan from Ajax and Adam le Fondre has also signed, the duo brought in to replace Adrian Mierzejewski and Bobo. Victory are much-changed, with the likes of Japan great Keisuke Honda and former Sweden international Ola Toivonen big-name arrivals as they look to fill the gaps left by the likes of Leroy George and Besart Berisha.

Can Melbourne City finally break through?

City Football Group's Melbourne club are still looking for a first A-League trophy. Under Warren Joyce, City finished third last season before bowing out in the Semi-Finals. With star forward Bruno Fornaroli back fit, City shape as again being contenders this season. Ritchie De Laet and Riley McGree have joined on loan from Aston Villa and Club Brugge respectively, while the signings of Mark Birighitti and Rostyn Griffiths may prove even bigger. Small moments are again set to be decisive and it will be a question of whether City can deliver when it matters most.

Will Popovic deliver long-awaited glory in Perth?

Perth Glory are two-time Australian champions, but the last of those successes came in 2004 – the final season of the National Soccer League (NSL). In the A-League era, Glory have been unable to produce, including finishing a disappointing eighth last season. But, there is once more fresh hope in Perth, the arrival of 2014 AFC Champions League-winning coach Popovic boosting Glory. Former Socceroos defenders Matthew Spiranovic, Jason Davidson and Ivan Franjic should give Popovic a platform to build from. At Popovic's former club, the Western Sydney Wanderers, former Germany, Liverpool and Bayern Munich defender Babbel has taken charge.

Can settled, quiet Jets go one step further?

Ernie Merrick's Newcastle surprised last season before falling just short in a Grand Final loss to Victory. As others have either been forced into or simply made changes, the Jets are largely settled. McGree has left, but they have added Brazilian Jair and former Mariners and Victory winger Mitch Austin. Central Coast have been the noisy rivals this off-season, but the Jets may be the ones shouting at the end of the campaign. Adelaide United and Brisbane Roar have also avoided drastic changes in the off-season.

Will Mariners and Phoenix close the gap?

Central Coast and Wellington Phoenix finished well back in 2017-18 – the Mariners missing the top six by 15 points. Now under Mike Mulvey, the Mariners have drawn attention through Olympic great Bolt, but signings like Ross McCormack – who scored 14 goals in 17 A-League games while on loan at Melbourne City last season – and Tommy Oar at least give fans in Gosford hope. The Phoenix, with Mark Rudan in charge, have added former Newcastle United defender Steven Taylor to their squad as they too eye improvement.