Marcos Alonso joined Chelsea from Fiorentina on transfer deadline day

Chelsea's £24m deal for former Bolton and Sunderland defender Marcos Alonso received a mixed reception, but there is logic behind the transfer. Nick Wright profiles the Spanish defender and explains why he could be a good fit for Antonio Conte's side.

Transfer deadline day saw contrasting signings at Chelsea. On the one hand there was the blockbuster return of David Luiz, a larger-than-life character back in west London after two years away, and on the other there was Marcos Alonso, an uncapped Spanish defender best known in England for spells at Bolton Wanderers and Sunderland.

Alonso's arrival from Fiorentina was predictably overshadowed in the media frenzy surrounding Luiz, but it is no less important. The left-back spot has been an issue for the Blues ever since Ashley Cole's decline and departure in 2014, with Cesar Azpilicueta forced to move across from right-back as specialist signings Filipe Luis and Baba Rahman failed to meet expectations.

Conte will be hoping the latest pretender can buck the trend, but the jury is out among supporters. Alonso comes from an illustrious footballing family, rose through the youth ranks at Real Madrid and has spent the last two seasons competing near the top of Serie A with Fiorentina, but eyes are more easily drawn to the less glamorous entries on his CV.

Alonso spent three seasons at Bolton between 2010 and 2013

Alonso suffered relegation to the Championship during his three-year stint at the Macron Stadium between 2010 and 2013, and he landed in another relegation battle when he was loaned to Premier League strugglers Sunderland just a few months after his move from Bolton to Fiorentina.

On the face of it, those curious chapters in his career don't exactly scream of a player destined for the Premier League's elite, but Alonso has left a positive impression wherever he has been, and there were clues about his potential along the way.

The 25-year-old won a fans' player of the year award in his final season at Bolton, and Alonso was similarly impressive at Sunderland. He was named man of the match after starring on his debut in their Capital One Cup semi-final first leg victory over Manchester United, and the Black Cats tried to sign him permanently after he helped them climb from 20th to 14th in the Premier League.

Alonso in action for Sunderland against Manchester United

Fiorentina could have cashed in. Instead, their manager Vincenzo Montella was impressed by Alonso's attitude in pre-season and made him a regular starter. He kept his place when Montella was replaced by Paulo Sousa in 2015, and he became well-known to Conte, too, lining up against his Juventus side on six occasions between 2014 and 2016.

Rather than possessing a single outstanding quality, Alonso's broad footballing education has helped him develop into an accomplished all-rounder. His marauding runs down the left flank became a feature of Fiorentina's playing style over the last two years, and last season he had the highest combined total for goals (three) and assists (four) among defenders in Serie A.

Alonso scored three Serie A goals in his final full season at Fiorentina

Those numbers will not have gone unnoticed by Conte, who likes to send his full-backs on the attack. Alonso has even become a dangerous set-piece taker, and he has defensive strengths too. He is particularly adept in the air, and he developed an intelligent reading of the game during his time in Italy.

"I've improved a lot in the last two years," he told Chelsea's official website. "Italy is like a masterclass for defenders. I used to play for Real Madrid and because you rarely had to defend there I used to work more on my attacking qualities, but in Italy I've improved defensively and also mentally."

Alonso has signed a five-year contract at Stamford Bridge (Picture: Chelsea FC)

Crucially for Conte, Alonso is also versatile. The Italian has used a conventional back four in his early weeks at Chelsea, but he generally prefers to use three at the back, and Alonso - like fellow new signing Luiz - gives his new manager plenty of options to switch things up.

"I've played in different positions over the last few years due to a change in managers and systems," he said. The Spaniard is at his most comfortable as conventional full-back in a 4-2-3-1 formation or a wing-back in a 3-5-2, but, at 6ft 2ins, he also has the physical stature to play as a central defender in a back three, where his much-improved distribution can be harnessed to build from the back.

Marcos Alonso's passing improvement Season Club Pass success % 2015/16 Fiorentina 83.4% 2014/15 Fiorentina 80.3% 2013/14 Sunderland 71.9%

Alonso is not a spectacular player and he is prone to the occasional lapses of concentration, but he offers tireless work rate, and his eclectic CV - he was only 19 when he rejected Benfica to join Bolton from Real Madrid - demonstrates an obvious willingness to learn. That's perfect for Conte, a reputed man-manager who specialises in ironing out his players' weaknesses - as long as they are fully committed.

Chelsea striker Michy Batshuayi has already said he feels like he is "progressing a lot" under Conte's guidance, and Alonso could be the next new signing to feel the benefits. The Spaniard has taken an unusual route to the top and he didn't cause much fanfare on Deadline Day, but he has a history of improvement. Under Conte, there might be more to come.

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