LONDON, ENGLAND - AUGUST 11:  Olivier Giroud of Arsenal celebrates following his team's 4-3 victory during the Premier League match between Arsenal and Leicester City at the Emirates Stadium on August 11, 2017 in London, England.  (Photo by Shaun Botterill/Getty Images)

The Five Things We Learned From Arsenal's Incredible 4-3 Win Over Leicester City

Well, what a welcome back to the Premier League that was! Arsenal's 4-3 victory over Leicester City on Friday evening is perhaps one of the most entertaining opening day fixtures since the league's inception in 1992. 

A game that was littered with entertainment, fans were treated to an incredible feast of action in a contest that kept swinging from one way to the next. 

Here are the five things we learned from a blistering start to the new season... 

5. Is Jamie Vardy Back?

Leicester City forward Jamie Vardy slayed Arsenal with ease at the Emirates on Friday evening, offering shades of his form from two years ago. The England man showed his predatory instincts to score from close-range after a Marc Albrighton cross in the first-half then notched a glancing header 11 minutes into the second-half from a Riyad Mahrez corner. 

Vardy started last season quite poorly, taking 13 Premier League games to reach two goals and he done it within an hour on Friday. Perhaps the pressure of holding the crown last season was to blame, but only time will tell if Vardy can re-ignite his form from 2015/16. 

4. Alexandre Lacazette Gets Off to the Perfect Start

The club-record £52m signing from Lyon scored with just his second touch in an Arsenal shirt. The France international headed from a Mohamed Elneny cross with just two minutes gone, paving the way for an incredible game to ensue. 

The 26-year-old beat Kasper Schmeichel from close-range after beating Wes Morgan to the Egyptian's cross. Gunners fans will be hoping this is just a small snippet of what is to come from Lacazette who is the fifth player to score on his debut under Arsene Wenger. 

3. Arsenal's Defending Leaves Food for Thought

Shipping three goals at home was not the ideal start Arsenal and Arsene Wenger wanted for the season opener. With that said, the north Londoners have shipped goals in their most recent curtain raisers so perhaps it was to be expected. 

Nonetheless, without their usual centre-back pairing of Laurent Koscielny and Shkodran Mustafi, the likes of Rob Holding and Nacho Monreal were naturally going to find it tough against Jamie Vardy and Shinji Okazaki. Even Petr Cech was caught out by crosses and long throws so improvement is needed. Fast. 

2. Harry Maguire Looks Destined for Big Things

Oddly enough, the £17m capture from Hull City was Leicester's best player despite them shipping four goals. It was a fine debut from Harry Maguire who showed plenty of hustle and bustle and even chipped in with an assist for the Foxes first goal. 

The former Sheffield United defender looked very much at home in the centre of defence and his commanding presence and suitably aggressive style will benefit Craig Shakespeare's side throughout the season. So far, so good from the 24-year-old. 

1. Olivier Giroud Is Just Simply Beautiful

He's got a knack for this, you know. Olivier Giroud has now scored seven Premier League goals whilst coming off the bench in the last calendar year. The Frenchman was introduced alongside the game's other super sub, Aaron Ramsey on 67 minutes and they both scored to give Arsenal a smash-and-grab victory. 

The 30-year-old striker will surely remain a key part to Arsene Wenger's side throughout this season, despite not being a guaranteed starter. The likes of Alexis Sanchez, Danny Welbeck, Alexandre Lacazette and Lucas Perez are all vying for the same position/s so Giroud will likely be reserved for super-sub missions.