The storylines that will define the second half of F1 2019

After F1's summer break, racing resumes at Sunday's Belgian Grand Prix, the first of the nine races left on this season's calendar. The shutdown is a good chance for employees to switch off and take a break from F1, but several storylines that will define this season are lingering.

Red Bull's Albon experiment

Red Bull has ensured it will be the centre of attention in the build-up to the Belgian Grand Prix following the decision at the start of August to promote Alexander Albon from Toro Rosso and send out-of-form Pierre Gasly in the other direction, just 12 races into his time with the senior outfit. It's a bold move -- it's easy to make an argument for demoting Gasly, given his form, but most expected Russian driver Daniil Kvyat would be the one to go up, leaving rookie Albon time to flourish out of the spotlight.

The decision actually makes some sense if you strip away the emotion and appreciate that this is all about evaluating the best man to partner Max Verstappen in 2020. Kvyat is a known quantity given his long stint with the company, including a year and a bit with Red Bull itself, but Albon is not. His elevation was labelled as a chance to evaluate the Thai driver in exactly the same scenario as Gasly.

It won't be a perfect comparison, of course. Albon will have a baptism of fire in quickly learning a new car -- Gasly had all of preseason to do the same -- and immediately facing up to the unenviable task of trying to match Verstappen on Saturdays and Sundays. He can take comfort in the fact the benchmark is not that high -- the closest Gasly got to Verstappen on a Saturday they both made Q3 was 0.314s, which is a lot in F1 terms.

Albon has impressed many in the first 12 races of his F1 career and many in the paddock who believe he has the potential to be a future world champion if he develops the right way, but this next few months could make or break his young career. If he can score the results Gasly was unable to in the RB15 he will stand a very good chance of keeping the seat for good.

As for Gasly, he will need to rebuild his reputation at Toro Rosso, the team he started his F1 career with in late 2017. Right now it's hard to imagine him ever getting another chance at Red Bull but you have to believe the team would consider giving him another chance if he was able to find form again in the midfield.

Ferrari vs Red Bull

The success or failure of the Albon promotion is likely to have a big impact on the fight for second position in the championship. Speaking after the Hungarian Grand Prix, shortly after stating it was Red Bull's intention to retain Gasly for the year, team boss Christian Horner said the Frenchman's wofeful form had left the team "one-legged" on too many occasions. Without two cars running at the front it has been difficult for the team to be aggressive with Verstappen's strategy.

With Albon at the helm, Red Bull will hope to have its other car running high up the order. Not only would that open up strategic options, it has the more obvious benefit of meaning the team can collect more points in the constructors' championship. It is 44 points behind Ferrari at this stage and those two teams look to be well matched, but the Italian team won't be a stationary target in the fight.

Ferrari has somehow got to this stage of the season without a victory but has two perfect opportunities to put that right immediately -- Belgium and Italy will suit the team's engine advantage. A victory at the Italian Grand Prix would be Ferrari's first at home since 2010. A Monza win would add a bit of gloss, at least, to what has been a very disappointing season.

Lewis closes in on Michael

At some point in the next three months, barring a remarkable turn of events, Lewis Hamilton is going to become a six-time world champion. That is an amazing achievement in its own right and it will move him to one title away from matching Michael Schumacher's all-time record (he's also closing in on the German's grand prix win tally of 91). Inevitably, that will raise the same discussions which started after Hamilton secured his fourth and fifth championships over the past two years -- is the Englishman the greatest to have ever driven an F1 car?

It can be a tedious debate as there's no clear answer, so a fairer question would be when exactly he matches and breaks Schumacher's two records. If he won each of the remaining races, he would finish the year with 90 career victories -- meaning his first next season would bring him level. A dominant run like that seems unlikely, but its not outrageous to suggest Hamilton can win four or five of the last nine.

Whichever way you look at it, in 2020 he should become F1's most decorated race winner, and by the end of the year could be level as the most successful world champion. Of course, he could do all of that with a new teammate...

Bottas, Ocon and the driver market

In Budapest Mercedes boss Toto Wolff said he would use the break to decide who will be Lewis Hamilton's teammate in 2020 -- his choice is between Valtteri Bottas or Mercedes junior Esteban Ocon. Bottas started the year strongly -- being dubbed Bottas 2.0 after winning the opener in Australia -- but his championship hopes have faded in recent months. He hasn't won since the Azerbaijan Grand Prix in April.

Ocon missed out on an F1 seat this season rather unfairly and Mercedes has to find a seat for him or risk losing him from their driver programme. Despite also having George Russell on the books, Ocon is too good a long-term prospect to let slip through Wolff's fingers.

If Bottas is retained, Ocon would surely land elsewhere -- rumours ahead of the break linked with Haas, while Renault remains a natural fit for the Frenchman. Wolff felt slighted by Renault boss Cyril Abiteboul last year after the team signed Daniel Ricciardo when Ocon appeared all set for a move, but surely he wouldn't let that get in the way of a loan deal which would allow him to keep the harmonious Mercedes atmosphere Lewis Hamilton clearly thrives in.

As with every driver market, moves up top will be significant in shaping next year's grid lower down the order too. Ocon to Haas would likely be at the expense of Romain Grosjean, while landing at Renault would spell the end of Nico Hulkenberg's time at the team. In that scenario, would Hulkenberg find a home at Haas, alongside his old rival Kevin Magnussen? Or would he find a seat elsewhere on the grid? And then there's the question of Alfa Romeo and whether it decides to give Antonio Giovinazzi a second season at the team.

Midfield: Can anyone catch McLaren?

McLaren has been the feel-good story of 2019 so far. A team on the ropes for the past few years, it has been comfortably best of the rest with Carlos Sainz and rookie Lando Norris at the helm -- its little surprise McLaren took itself out of any driver market rumour stories by confirming that line-up will remain unchanged for 2020. At the break, McLaren was fourth, 39 points clear, with the chasing pack all closely matched lower down.

While McLaren has excelled its engine supplier, Renault, has had a very difficult first half to the season with its factory team. Renault made a big splash for Ricciardo and his signing was a huge statement of intent, but so far the French manufacturer has not matched that with results on track. Being unable to match McLaren is especially hard to stomach as it reflects very poorly on car design, but in taking two wins with Red Bull already Honda is also clearly making the kind of progress Renault is not on the engine side. The other Honda-powered car, Toro Rosso, sits in fifth place above Renault currently, but it's fair to wonder whether the driver swap mentioned above will have an adverse impact on its season.

Alfa Romeo is still in the hunt, although it is hampered by the fact Antonio Giovinazzi has scored one point to Kimi Raikkonen's 31, while Racing Point has looked closer to the back of the pack than the midfield in recent months. And then there's Haas in ninth position...

Can Haas solve its problems?

Haas has been at sea for the past few months. The American team has been genuinely stumped by its car's lack of pace, with the car often able to qualify well before fading dramatically on Sundays. If you take away the crazy German Grand Prix, which was something of an anomaly, Haas has not scored a point since the Monaco Grand Prix in May.

A lot of its problems have been wrapped up in its tyres and the team took the unusual step of letting Romain Grosjean revert back to the specification of car it ran at the opener in Australia, stripped back of all upgrades which have been added since. That allowed the team to make a valuable comparison between its old and new spec, but it will have to run the updated car for both drivers in Belgium and Italy.

The most frustrating thing for the team is it hasn't produced a bad car in the conventional sense, as it has still shown glimpses of the sort of pace many expected from the American team when it left winter testing looking like the team to beat in the midfield. Team boss Guenther Steiner has called the issue the most difficult he's ever encountered in F1.

"If you have a bad car you get a big problem, but if you think with the car which sometimes performs the problem is smaller, it is even bigger [problem]," he said in Hungary. "Because it is somewhere, and you just need to find it, and it is difficult."

As ever in F1, hanging over everything is that one year bleeds into the next -- struggles to understand this year's car could have an impact on the team's 2020 model. A season which at one point looked so promising could really unravel over the next few months if Haas is unable to find answers to its problems in the coming months.