4 Things We Learned From Chelsea's FA Cup Semi-Final Victory Over Southampton

Chelsea will face Manchester United in the FA Cup final on 19th May, after the Blues won 2-0 against Southampton in Sunday's semi-final at Wembley - courtesy of a wonder goal by Olivier Giroud and a trademark header from Álvaro Morata.

Their win wasn't without its controversial moments - most notably the referee's decision not to use VAR before ruling out a Saints equaliser for an alleged foul on the Chelsea goalkeeper.

Yet it was still an impressive display by the Blues, with Hazard and Giroud both in top form, while Saints manager Mark Hughes may wonder what might have been if he'd adopted a more positive tactical approach from the start of the match - rather than waiting until Chelsea had already taken the lead.

Here are four things we learned from Sunday's clash.

1. VAR Isn't Going to Solve Everything on its Own

Well, we already knew that, but one particular incident on Sunday showed two reasons why VAR isn't going to save us from endless post-match post-mortems about contentious decisions.

Chelsea keeper Willy Caballero made a terrible hash of collecting the ball as Southampton striker Charlie Austin challenged him in the air. The ball crossed the line and it seemed the Saints had levelled the match - only for referee Martin Atkinson to penalise Austin for a foul on the keeper.

The first problem here is that, according to existing rules, the VAR couldn't even be consulted unless Atkinson was in any doubt about whether or not a foul had been committed - which he wasn't.

The bigger issue is that, no matter how many times you viewed the TV replay of the incident, there were still two possible interpretations. According to the letter of the law, Austin had fouled the keeper; but according to the spirit of the law, the striker had made a fair challenge and the keeper had made a calamitous error.

VAR may be a valuable tool for identifying incidents that the referee might have missed. Unfortunately for the Saints, this wasn't one of them.

2. Parking the Bus Only Works If You Defend Impeccably Throughout the Match

Hughes' decision to play two strikers up front created the illusion that he was adopting an ambitious, forward-looking approach. Yet in practice the Saints played most of the first half in an 8-0-2 formation.

This is a legitimate tactical approach - albeit a profoundly boring one for the neutral - but it only works if your players maintain optimal concentration for every second of the match.

Yes, Olivier Giroud's goal was a strong contender for goal of the tournament, but as for the defending which led up to it...

Well, let's just say that Alan Hansen would have had a field day if he were still a pundit. "Diabolical!"

3. Olivier Giroud Is More Adept at Dribbling Than You Might Have Thought

We all knew about Giroud's aptitude for opportunistic goalscoring and his strength in the air. However, until Sunday's clash, few observers would have had him down as an outstanding dribbler.

Yet he mesmerised Southampton's defence with his silky skills and magnetic close control, breaking the deadlock and forcing Southampton to abandon Plan A - which was a great relief for neutrals who had sat through the Saints' bus-parking exercise in the first half.

The France striker already looks like an excellent acquisition for Antonio Conte's side, while Arsenal fans may wonder whether offloading him was such a wise move.

4. Chelsea Should Do Everything in Their Power to Keep Eden Hazard

Yes, it's true - if Real Madrid come calling, it's very difficult for any player anywhere in the world to say no. That being said, if there's any chance of persuading Eden Hazard to stay at Chelsea, the Blues should do their utmost not to lose him.

The Belgium maestro was the best player on the pitch by some distance against Southampton, popping up everywhere and relentlessly tormenting the Saints defence, always looking for the chance to shoot or create an opportunity.

In fact, it was his sublime control and pass which enabled Giroud to show off his silky skills and net the opener.

Without Hazard's creative spark and ability to pass and move between the opponent's lines, Chelsea may well have struggled to unlock Southampton's stubborn defence on Sunday.