Hindsight will be playing havoc with the British and Irish Lions after Saturday's narrow loss in the series decider against South Africa.

It was within the Lions' grasp but they gave away needless penalties, they kicked to the corner when they could have gone for the posts and there were missed tackles.

They will be very frustrated and it will all be rattling around their head on the plane home.

Lions tours stay with you. I still feel we should have won the Test series against Australia in 2001.

We were left feeling it should have been 2-0 after the second Test and I wonder whether that was playing on the Lions' minds after South Africa levelled the series last weekend.

'There will be regret'

With the enormity of these games, there has to be an assumption that it is going to be won by fine margins.

From a northern hemisphere perspective, Lions Tests are the biggest games in rugby alongside World Cup finals.

The Lions had umpteen opportunities and they did not take them.

In 1997 the second Test was won by three points, in 2001 the decider was six points, in 2009 the second Test was three points, 2017 was a draw and now they have lost by three points in the decider. That is just the way the game is.

The psychological shift of being three or six points ahead in those types of games is absolutely enormous. Everything is so heightened.

They gambled once by kicking a penalty to the corner instead of taking three points and scored a try through Ken Owens.

Then they went for it another two times and got turned over. They did it again in the second half and were giving sloppy penalties away.

The Lions were in control but came away with next to nothing.

Some of that decision-making under the most extreme pressure was not quite as clinical as it has been in other big games for those big players.

There will be regret. I hope they had as good a time as they could away from the rugby pitch with all the strict coronavirus restrictions.

It will be nowhere near as memorable and special than if they had got themselves a victory on Saturday.

'Not an epic Lions series'

Overall, it was not an epic Lions series but I think the third Test brought it round a bit.

Given what was at stake, I thought it was a good game of rugby. I was on the edge of the sofa throwing my hands in the air in frustration or celebrating a kick - it had me.

The second Test was so dull. The same with the first half of the first Test, then it kicked off in the second half.

There were six tries across all three Tests. We cannot keep watching top-level international rugby like that. That is not going to attract enough people for the sport to blossom.

When you come into World Cup finals and Lions tours there is always going to be an element of that because there is so much at stake.

The third Test did not necessarily have the tries but it was at least fast, furious and intense.

It was made sterile by the fact there was nobody in the stands. If that had been a full house I suspect we would all be saying what an incredible Test match it was.

You do not have that emotional roller-coaster that you do when you are watching with a crowd.

'The bigger the game, the better Russell is'

One of the themes that will always be around the Lions is Test match animals and Finn Russell is one.

The bigger the game, the better the player he is. You cannot put your finger on why.

You are going to see him make some rubbish decisions in the club game or maybe in the odd Scotland fixture, but for whatever reason when intensity and pressure are at their maximum, it works for Russell.

He came on when Dan Biggar was injured after 10 minutes and South Africa were worried every time he got the ball.

It is impossible to mark him because he has all options open. Russell is one of those players that can unlock the opposition at the most pressurised moments and he has now got to understand how he can get himself to that level more often.

'Lions have been through a lot of mental stress'

There was so much uncertainty about whether the tour would go ahead because of the pandemic and the Lions have been playing in a strict coronavirus bubble for the last eight weeks.

The mental stress they have had to put themselves through will stand them in great stead for the rest of their lives.

They will reflect on that two or three-month period thinking, 'How did we get ourselves through that?'

The clubs and unions have now got to make sure that they look after those players mentally and physically.

They need to make sure they do not bring them back too early not just because of the physical side of it but the mental side because it could have long-term ramifications if they return too soon.

Above all the result and disappointment, the Lions have excelled themselves.

To get the players through safely and to sacrifice what they have - not just the players but the backroom staff and the admin staff - is incredible. Coming so close given the circumstances is absolutely remarkable.

It has whet the appetite for another four years.

Matt Dawson was speaking to BBC Sport's Becky Grey.