Tomas Kalas and the Best Debut Performances in Football
Defender Tomas Kalas was given a Premier League baptism of fire by Jose Mourinho on Sunday, making his debut against Liverpool and their free-scoring front line.
However, Chelsea's 20-year-old Czech rose to the occasion and put in a competent and commanding performance, helping contain Luis Suarez et al in the Blues' 2-0 victory.
Kalas inspires our list of some of the best debuts in world football...
Shortly after his £26.5 million move from Everton, Wayne Rooney made his Manchester United debut in a Champions League clash with Fenerbahce.
The 18-year-old striker immediately showed his worth, scoring a hat-trick and earning an assist in the 6-2 victory.
Borussia Dortmund's lightning-fast forward Pierre-Emerick Aubameyang made his Bundesliga debut for the Germans on 10 August, 2013 at Augsburg.
The Gabonese international promptly scored with his first shot and added two more to complete a hat-trick.
After a protracted summer saga, Gareth Bale eventually made his way to Real Madrid in September 2013, becoming the most expensive player in the world in the process.
The Welshman had an incredible amount of pressure placed upon him, but he got off to a dream start by scoring on his debut against Villarreal.
Manchester United midfielder Jesse Lingard was sent out to loan at Birmingham at the beginning of the 2013-14 season.
In his debut match against Sheffield United, he needed only 13 minutes to score a hat-trick and added a fourth goal in the second half.
Clearly impressed by his antics in the midlands, United called him back to their squad in January.
When Portsmouth were relegated in 1988-89, striker Micky Quinn made the move to Newcastle. On his debut for the Magpies at St. James Park in August 1989, he scored four times in a 5-2 victory over Leeds.
The notoriously tubby forward—described as the "fastest player over one yard"—went on to be the league's top goalscorer that season with 34 goals.
In the summer of 2013, Colombian striker Fredy Montero went on loan from the Seattle Sounders to Sporting Lisbon.
His first match was against Primeira Liga newbies FC Arouca, and he managed to score a hat-trick in a 5-1 victory.
So impressed were Sporting by Montero that they signed him on a permanent basis in January.
With Juninho, Emerson and Fabrizio Ravanelli on their books, Middlesbrough were an exciting prospect in the 1990s.
The Italian striker arrived at the start of the 1996-97 season and had an immediate impact, scoring a hat-trick against Liverpool on the opening day of the season.
Thanks to the White Feather, Boro reached the League Cup and FA Cup finals that season, but they lost both and were relegated when the FA deducted three points after they failed to fulfil a fixture.
Alan Shearer made his senior debut in a substitute appearance for Southampton against Chelsea in March 1988.
A fortnight later, the Geordie forward made his full debut against Arsenal, where he scored three goals in a 4-2 victory for the Saints.
At 17 years and 24 days, Shearer became the youngest player in top-flight history to score a hat-trick.