Fernando Alonso says McLaren has been able to surprise its rivals and itself with a step up in performance over the middle chunk of the 2016 season and is optimistic the form can be maintained at Spa.

Despite its unfancied Honda power unit against its rivals, both Fernando Alonso and Jenson Button have been able to battle competitively in the midfield at a range of circuits with different characteristics, including scoring points a power-depend tracks in Austria and Germany.

READ: When F1 fell out of love with the Belgian GP

Spa-Francorchamps represents another power hungry circuit on the F1 calendar - followed swiftly by Monza for the Italian Grand Prix next weekend - but Alonso feels McLaren's recent results give the team optimism that it won't be left behind on the straights.

"More than 70 per cent of the lap is spent at full throttle, which will be a challenge in itself, but we've shown over the past few races that, even on the circuits that statistically should be difficult for us," Alonso said. "We've worked hard and surprised ourselves with our level of performance relative to our competitors.

"Spa is a long lap, with two very high-speed sections and a twistier section, so we have to find the right balance between the two to get the best car set-up. We're seeing good correlation between the data back at base and in the car on track, so I hope we can continue our momentum and get the maximum out of the weekend.

"This circuit is always a tough challenge for car and driver but if we can pull all the elements together we can enjoy a positive weekend. It won't be an easy race, but as always we'll be pushing for points as hard as we can."

VOTE: Who's going to win the Belgian GP?

Despite Alonso's prestigious F1 career the two-time world champion has never won at Spa-Francorchamps. With a maiden victory looking unlikely given McLaren's performance, Alonso will be aiming to collect more points for the Woking-based team as it looks eat up the three point gap to Toro Rosso for sixth in the F1 world constructors' championship.