Formula 1: Sebastian Vettel needs to keep firm pressure on Lewis Hamilton in Germany

Sebastian Vettel needs to keep the pressure firmly on Lewis Hamilton at this weekend's German Grand Prix. At the midway point of the Formula One season - the 11th race out of 21 - Vettel holds only an eight-point lead over rival Lewis Hamilton in an intriguing title contest.

Vettel started strongly, then Hamilton took over, and now Vettel appears to be in the ascendancy again. While he leads Hamilton only 4-3 in wins this season, Vettel's most recent victory was particularly poignant seeing it was at Hamilton's home track at Silverstone - where Hamilton has enjoyed huge success. Vettel's win there heaped more misery on the British driver, considering he'd experienced a rare retirement at the Austrian GP one week earlier.

In previous years, Ferrari was the team experiencing technical problems and frustrating inconsistency. Now the roles appear reversed, and Mercedes is the team under pressure. Having won the last four drivers' and constructors' championships, often by huge margins, Mercedes lags 20 points behinds Ferrari. There have been communication errors and strategy mistakes within Mercedes.

For Hamilton, who along with Vettel is vying for a coveted fifth F1 crown, these problems are hard to accept. Last year, the pressure seemed to affect Vettel more, but this time Hamilton is the one showing signs of strain. Rapidly overtaken from pole position at the British GP, Hamilton was then shunted off the track following a collision with Ferrari's Kimi Raikkonen.

After Hamilton fought back brilliantly from last place to an impressive second place, he made comments about Ferrari's "interesting tactics" - implying Raikkonen had done it on purpose as part of team strategy. Hamilton subsequently apologized, calling his own comment "dumb." While Vettel has upped his level from 2017, Hamilton has still shown his trademark speed and consistency, aside from a poor start at Silverstone.

Mercedes has often taken the blame for Hamilton's setbacks, right up to the top. "We've left points on the table and had to do damage limitation more often than we would have wanted," said Toto Wolff, the head of motorsport. "A lot of that was down to our own mistakes."

With Mercedes wobbling, and Hamilton getting agitated, the timing seems right for Vettel to strike another blow at Hockenheim on Sunday. The German race is returning after being dropped last year for financial reasons. Home fans will be in the unusual position of cheering a German driver (Vettel) in an Italian car, competing against a British driver (Hamilton) and his Finnish teammate Valtteri Bottas in German cars.

If any one of the three wins, it will feel like a victory for Germany. "Going to Hockenheim always feels like coming home," Wolff said. "It's only about a 90-minute drive from the Daimler headquarters in Stuttgart."

The Hockenheimring, as the circuit is called, is in in southwest Germany's Baden-Wuerttemberg region which borders with France. It features fast straights in the first half of the 4.6-kilometer (2.85-mile) track, meaning fans can hope for a thrilling 67-lap speed duel between Mercedes and Ferrari. But Red Bull is waiting to pounce.

While Red Bull is not as quick as its main rivals, the gap has been closed this season, and Daniel Ricciardo and Max Verstappen have three victories between them. Ricciardo has won two, while Verstappen is driving impressively after a rocky start.

The 20-year-old Dutchman - the youngest to win an F1 race and to qualify on the front row aged just 18 - has four podium finishes in the past six races and is showing the kind of form which earned him a bumper new contract last year.