McLaren believes five teams will be separated by almost nothing in the fight for third in the Constructors' Championship in 2021.

Last year, just 21 points covered the Woking-based team, Racing Point and Renault in a midfield duel that went all the way to Abu Dhabi, with McLaren eventually coming out on top.

However, team boss Andreas Seidl thinks holding on to that position this year looks like being easier said than done, despite McLaren switching to Mercedes engines for the upcoming season.

“I think it will be again a battle probably between four or five teams,” he told Motorsport.com.

“For this P3 to P7 fight, it will be similar to what we have seen this year [2020]. So simply we need to stay realistic about what is possible.

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“On our side, we still have these big restrictions with an outdated infrastructure and it will take three years until we have all the updates in place, then it takes time also to get this infrastructure actually to a place where you see the benefits from it.

“Until then, we simply have restrictions. But nevertheless, there’s still more potential in the team already now, and that’s what we try to lift or explore for next year.”

McLaren CEO Zak Brown then assessed their main competition for 2021.

“When you see where [Charles] Leclerc ended up in the championship if they [Ferrari] had a more consistent second driver, I don’t think they would have finished sixth,” he was quoted by PlanetF1.

“That is why I think that with their resources in 2021 they could definitely pose a threat to third place.

“Racing Point [now Aston Martin], in my opinion, had the best car in the midfield most often and I think [Sebastian] Vettel, as a four-time world champion, definitely has it in him. Ferrari wasn’t a great environment for him anymore, for whatever reason.

“You have to assume he can pick up where Sergio Perez left off at Aston Martin if that’s a good environment for him.

“Renault [now Alpine] was the third-fastest car every now and then last year and Fernando [Alonso] is faster than he’s ever been, so he’ll also drive at the front of the midfield," he continued.

"Esteban Ocon had a tough time in 2020, but at the end, he wasn’t far off the level of [Daniel] Ricciardo.

“AlphaTauri, you can’t count them out. They always want to race, but in 2020 they didn’t really have a consistent driver duo.

“I don’t know much about Yuki Tsunoda, their new driver, but he seems to be very good. Gasly has always been good at AlphaTauri, so you definitely have to take them into account.

“I think there will be a maximum of one or two-tenths of a second between those five teams. It’s going to be a great fight for third place.”

Before then, however, Seidl reflected on McLaren's best championship finish since 2012 last year.

“I’m very proud to be part of the McLaren F1 team and I think every single member of the team can be very proud of what we have achieved this year,” he added.

“It was quite challenging with the pandemic kicking in. We lost a lot during this period, but with the great talent we have in the team, and with the commitment everyone has shown, it’s something I’m very happy with obviously.

“It was very encouraging to see, and shows that we are heading in the right direction and that we can also make the next steps as a team in the coming years.”