McLaren believes the next few months will be 'crucial' for his team's chances this season.
Alonso finished 5th at the Australian Grand Prix, but the former world champion is realistic of the team’s chances, saying:
"There is still a lot to improve to catch the top three teams
"It's quite a reasonable gap to close but it is up to us now."
McLaren have switched to Renault engines this season following three seasons of poor performances with a Honda engine. Alonso and his teammate
Stoffel Vandoorne both finished in the points in Melbourne and the Spaniard is looking forward to the rest of the season, saying:
"The next two months are crucial for us. If it is not a world championship fight, it will hopefully be some podium positions.
"It is probably the first time in the last three years it is up to us - the car has the potential.
"We had some ups and downs in testing and then in Australia it was the same thing and the qualifying was not smooth enough to show the potential. It was a good race, help from the safety car, but we take this fifth place and move on.
"It is up to the team to deliver the performance in the next four, five, six races."