Awkward 2013 tweets from Luke Shaw about Cristiano Ronaldo resurface

Luke Shaw has risked Cristiano Ronaldo 's wrath as his nine-year-old tweets about the Manchester United superstar have come to light.

The duo have been teammates since Ronaldo, 36, dramatically returned to Old Trafford in a £20million transfer from Juventus last summer.

But the Portugal captain will be less than pleased to discover Shaw's take on his famous rivalry with Lionel Messi and verdict on his goalscoring prowess.

The defender, now 26, held little back in tweets posted while he was a teenager bursting onto the scene for Southampton that have subsequently been deleted.

Shaw was writing after Real Madrid defeated Barcelona in the Copa del Rey semi-finals in 2013, with Ronaldo scoring twice in the second leg at Camp Nou to fire Los Blancos to a 4-2 aggregate victory.

Who is the greater player out of Cristiano Ronaldo and Lionel Messi? Have your say in the comments!

He wrote: "Not really a Ronaldo fan but fair play to him tonight. [He has] Always been in Messi's shadow, but the way he is playing at the moment is unstoppable."

Ronaldo put Real Madrid ahead from the penalty spot in the first half and added his second of the match shortly before the hour mark.

Then managed by Jose Mourinho, Los Blancos kept Messi off the scoresheet to eliminate the defending champions and reach the final, where they were defeated by local rivals Atletico Madrid.

Shaw faced criticism from other social media users for his remarks about Ronaldo, but he was adamant Messi is the greater player and pointed to his world-record 91-goal year in 2012 to illustrate his point.

When asked what Messi can do that Ronaldo cannot in March 2013, the Englishman hit back: "[He has] Scored 91 goals in one year. Has Ronaldo done that?"

Shaw's criticism of Ronaldo actually dates back even further to the previous year, when he was called out by a Twitter user following Ronaldo's remarkable brace to send Portugal past the Netherlands and into the quarter-finals of Euro 2012.

Upon receiving a tweet asking if he was watching Ronaldo "take the p*** out of Holland", Shaw replied: "Look at you begging him because he had one good game. Messi does it all the time! Now shhh #TeamMessi."

Shaw may have revised his opinion on the debate between Messi and Ronaldo since he started training and playing alongside the latter.

Speaking to BBC Radio 5 Live in October, the Three Lions star declared it is "unbelievable to be in a dressing room" with the five-time Ballon d'Or winner.

Shaw added: "It's clear to me why he (Ronaldo) has been at the top for so many years. His mentality is second to none."