Fernando Alonso believes McLaren's hopes for this season will be defined by a "crucial" two months as he urges the team to push on the development front.
After finishing fifth at the opening race of the season in Melbourne, Alonso said McLaren can focus on cutting the gap to fellow Renault customer Red Bull in coming races.
"I think it's still quite a reasonable gap to close with the leaders, but I think it's up to us now", he said.
"It is up to the team to deliver the performance in the next four, five, six races".
"For me, I believe the next two months are crucial for us in this year's championship - and if we are not fighting for the championship itself, then we are for regular podiums and finishes in the top six".
McLaren has cited its ambition to return to the rostrum at some point this season, a target Alonso shares having gone nearly four years without recording a top three finish; he hopes added performance will make top five positions a regularity.
"I was on the podium in 2009 with the introduction of KERS and that auto that we were, I think, ninth in the World Championship or something like that, and I was on the podium so anything can happen in F1". Maybe P5 could become the normality - that is something that we need to discover and find out.
'It is probably the first time in the last three years it is up to us - the auto has the potential'.
Despite a mid-race Safety Car in Australia, Alonso finished 21.5 seconds off the final podium place but the Spaniard is adamant McLaren can finish in the top three in 2018. The two-time world champion responded with a reminder of his career history.
"We have some new parts here".
"Anything can happen in a race".
"Anything can happen in F1". 'If you are close to that position, sooner or later that opportunity will come. "I think it is very possible this year".
Alonso admitted that his fifth place in the opening race owed something to luck, after he gained several places thanks to the intervention of the virtual safety vehicle, which also decided the lead battle between Mercedes' Lewis Hamilton and Ferrari's Sebastian Vettel.
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