Twin terrors for Vettel in Hamilton and Leclerc

The 2019 season could prove pivotal for Sebastian Vettel. It's been five years since Vettel's fourth world championship, which he won in another F1 era and with a different team, before the series' switch to its modern hybrid power plants.

All-conquering Mercedes and Lewis Hamilton triumphed as a series of errors blighted Vettel's 2018 title challenge, particularly in the second half of the season, prompting personnel changes in the garage and the cockpit for the Scuderia ahead of the new season.

New kid on the block

Mattia Binotto has taken charge of the team, while 21-year-old Charles Leclerc replaces Kimi Raikkonen in the second scarlet car. The Monaco native, who caught the eye with a series of improbable performances for Sauber during his rookie campaign, could prove much more than a youthful rear gunner for Vettel.

"He's smart, he's quick," Binotto told Italian paper Corriere della Serra in the run-up to Sunday's opening race in Melbourne. "We will have a lot of joy with him."

Before a wheel's turned in anger, Binotto is already hedging his bets on the status of his two drivers within the team. Despite saying that the pair will be "free to fight" in the opening races of the season, he's also said that the initial focus will be on securing a title with Vettel at the fifth attempt.

"Sebastian has more experience, he's been with us for many years, he's won F1 championships," Binotto said. "So he's our champion."

With Michael Schumacher, fifth time was indeed a charm during his Ferrari tenure. Once the first title came, he went on to win five in a row.

Hamilton still the favorite?

Despite all the changes at Ferrari, and the Italian outfit's impressive showing in pre-season testing, Lewis Hamilton and Mercedes still pose the primary threat. Mercedes have won every single drivers' and constructors' championship since the major rule changes of 2014.

Now 34, and champion in four of the past five seasons, Hamilton will be seeking a sixth drivers' title. Already assured of a mention among F1's very best, the Brit must surely have at least half an eye on the records of Michael Schumacher. He's 18 race wins and two championships shy of Schumacher's tally, and has already started more F1 races from pole than anybody in history.

Having sat back and concentrated on longer runs with heavy fuel loads for the vast majority of testing, leaving Ferrari to dominate the timesheets as the teams prepared in Spain, Hamilton turned the wick up on the last day of testing.

Instantly, he was able to put down a lap time just 0.003 seconds slower than Vettel's fastest of testing - demonstrating that even an improved Ferrari cannot expect to waltz off unchallenged in Australia.  

"The regulations have changed quite substantially," Mercedes boss Toto Wolff said at testing. "So we have to start from scratch, to prove ourselves again, against our own expectations and against our competitors. There's absolutely no feeling of entitlement to be at the front."

Clipped wings for improved racing?

Wolff even insinuated that major aerodynamic rule changes - focusing on cars' front and rear wings - might be a deliberate attempt to rein in Mercedes and force them to give up some of their advantage over the field.

Nominally though, the alterations are designed to promote closer, more exciting racing. The new car dimensions are supposed to reduce the performance disadvantage drivers encounter when following another car closely. In theory, if it's easier to follow and keep pace with a car, then it should be easier to overtake as well.

Veteran Sergio Perez at Racing Point F1 (formerly the Force India team) was cautiously optimistic about the changes after lapping behind a Mercedes in testing.

"I did a bit with [Valtteri] Bottas," Perez said. "Certainly I feel that you lose less downforce … We will see in Melbourne really, what it's like racing with other cars around you with similar pace and so on, but I really hope the show can be a lot better."

Red Bull — wild cards, or more?

Dutch charger Max Verstappen had few problems overtaking even under the old rules at several races. His Red Bull team, and talented new French teammate Pierre Gasly, will also hope to mix it at the very front during the course of the season.  Staggeringly, the team's drivers have an average age of 22.

As in recent years, the early evidence points to a Red Bull that might not quite rival Ferrari or Mercedes in the round, but of a car that could excel at circuits playing to its strengths: cornering speed, maneuverability, traction and tire preservation.

Having switched from Renault to Honda power, Red Bull again appear to be the wild cards on the grid. The team's fastest times in testing at Barcelona were set on only the third-fastest tires available — meaning the Milton Keynes crew has done its best to keep its true potential for qualifying in Melbourne under wraps.