The Mercedes Formula 1 team was left encouraged from the early signs shown by its latest engine upgrade during practice for the Belgian Grand Prix.

2018 title rivals Mercedes and Ferrari both debuted new power units at Spa in the hope of achieving a welcome power boost as F1 resumed following the summer break, with the two teams split by just 10 points in the constructors’ championship.

Despite currently holding a points advantage, the reigning world champions have often appeared to trail Ferrari in engine performance this season and were keen to find a response for the final nine rounds.

Belgian GP - Memorable Moments

Mercedes delayed its first major engine update from Canada to France due to concerns over reliability, but having run its latest specification on Friday, the German manufacturer was left satisfied by the updates.

“We've brought a new engine today and everything was running smoothly,” said Hamilton, who ended FP1 third-quickest behind Sebastian Vettel and Max Verstappen before improving to get within 0.168s of Kimi Raikkonen’s session-leading time in FP2.

The Briton holds a 24-point advantage over chief title rival Vettel but is anticipating another close battle for supremacy between Ferrari and Mercedes this weekend.

“It's really close between us and Ferrari; it seems like we've both been bringing new updates at a similar rate,” he explained.

“For the middle sector, you want to have a good amount of downforce, but you want less in the other sectors to gain speed down the straights. The challenge is to find the right balance and thankfully I have a great team working on that.”

Technical chief James Allison backed up Hamilton’s comments about Mercedes’ new engine, but stressed the team still has work do do over long run simulations after both drivers struggled to piece together a solid programme.

“Both drivers at various points of both session looked quick and that the new engines ran reliably and showed a promising performance,” Allison said.

“The area where we need to do more work is that the long runs were poor and scrappy affairs with both drivers. A mixture of traffic and flat-spotting meant that we didn't establish the rhythm that gives you a warm feeling going into Sunday.”

Valtteri Bottas was shaded by Hamilton in both sessions and will start from the back of the Belgian Grand Prix grid after exceeding his quota of permitted engine components following the introduction of Mercedes’ new power unit.

“Ferrari looked a little bit quicker in some corner combinations like Turn 5 to Turn 7, but I don't think we're far off,” The Finn said. “However, it's always difficult to make any detailed predictions on Friday for the weekend as it is usually really close in qualifying.

“Fortunately, the long-run pace felt good and I am confident that it is possible to come up through the field here in Spa. The new engine also felt good today, so I'm looking forward to the race - it should be fun.”