While broadcasting from the Estádio da Luz in Lisbon during Euro 2004, I declared in my closing link to the viewers on ITV that Greece had qualified for the quarter-finals. This was after I had heard someone in my ear say so. Only they didn't actually say it to me, I was ear-wigging. Technically I would eventually be right, but at that moment it was mathematically not a done deal. The show ended without a chance for me to add my caveat.

Brian Barwick, my boss at the time, ticked me off on the bus back to the hotel. Worse still, he ticked me off in front of Des Lynam. So a lesson was learnt; never announce a winner, never declare a goal if you are not prepared to put your house on it. And if you're going to get told off, try to make sure that it's not done in front of a broadcasting legend. As we head into the final weekend of football's and rugby union's top leagues, I thought it was worth remembering that lesson.

While Manchester United simply have to win at Wigan Athletic to be sure of retaining the Barclays Premier League title, more work is needed for those statisticians presiding over rugby union's Guinness Premiership.

You may say that this isn't the final weekend because that comes at the end of May and only after the top four have played off against each other. I am a convert to the play-offs and would argue that this league is great value for money - a double climax if you like.

Whole pages on rugby websites are being devoted to what needs to happen to whom at what point this weekend to finish second, third and fourth. So put it this way: even if London Wasps beat Leeds and get a bonus point, they will still be looking at the match between Gloucester and Bath to see if they finish second, Harlequins will have to beat Leicester and then they'll be looking to Sale Sharks to slip up against London Irish.

The play-offs divide opinion, but as things stand they are the only fair way of balancing out the impact the Six Nations Championship and autumn internationals have on the clubs, although I am sure that this wasn't the main motivator at the start. If you are losing six or seven first-team players to internationals every week for a six-week period, it is going to hit your league form.

In the final England match of the Six Nations against Ireland, five Wasps players turned out for the home team (and one for Ireland), compared with two Gloucester players. It's no wonder that Wasps found themselves eighth in the table at the start of March. While Danny Cipriani was being hailed as England's new hero, he wasn't kicking goals for Wasps.

Now, Wasps have an amazing team spirit and they have a habit of unearthing fine youngsters at the right time, but if you lose six regular first-team players you will notice a difference. But as Shaun Edwards, the Wasps head coach, says, “you don't win trophies at the start of the season”. Thank God for that because if the league finished at Christmas, Wasps would have won little for the past eight years. Yet three times from 2003 to 2005, Wasps won the title while never finishing top of the league.

If the intricacies of the Premiership title race leave you flustered, the Premier League is for you; two teams left in it and one match left. It's gloriously simple. Boring, Kevin Keegan says; he didn't say that when it was a two-horse race in 1996. I wonder if he'd prefer a play-off system. Anyway, a two-horse race on the last day of the season is good going in a league where there are so few contenders at the start; the only thing to play for on the last day of 2006-07 season was survival.

This time we have three teams fighting for one survival spot. Fulham are the team with energy and momentum. They timed their escape from the bottom three to perfection, getting out of the drop zone for the first time this year only last weekend; if the laws of physics can be applied to football, they would survive.

They are the only team with control over their destiny - beat Portsmouth and they retain Premier League status. If they don't win or they draw, they will need to hope that Reading and Birmingham City slip up, too. Strange things start happening in your head at this stage in the season; relegation is arguably much more emotional for the neutral than the two-horse title race.

The beauty of sport is encapsulated in this final weekend. For all the efforts, all the miles travelled and all the pain of supporting your team it comes down to this, to 80 or 90 minutes of nail-biting, of holding your head in your hands and realising at half-time that you forgot to breathe in the first half. And if that's you this weekend, good luck.

If it doesn't work out, try to treat the twin impostors of defeat and victory the same, and if you just can't, cry your heart out - it always helps.