Chelsea are one of the most successful English clubs since the turn of the century.Since their takeover by Russian oligarch Roman Abramovich in the early 2000s, Chelsea have consistently been in the Premier League's top echelons and have regularly rubbed shoulders with Europe's best.Unsurprisingly, some of the finest players in the world have turned up for Chelsea over the years, especially in the last two decades.Five players who are seemingly surplus to requirements at ChelseaAfter finishing a creditable fourth in the 2019-20 Premier League despite their two-transfer-window ban, Chelsea carried out one of the most expensive squad overhauls in the game this summer.Chelsea managed to address most problem areas in their roster by roping in a mix of youth and experience from around the continent. However, this influx of new players, coupled with a loss of form and injury, have meant that a few players have slipped down the club's pecking order, finding regular first-team football difficult to come by in recent times.On that note, let us have a look at five players whose futures may lie away from Chelsea.#5 Danny DrinkwaterDanny DrinkwaterDanny Drinkwater was one of the standout players in Leicester City's Premier League triumph in 2015-16. A season later, Chelsea came calling. However, the player has been a pale shadow of his illustrious self at the London club. Drinkwater has struggled big-time at Chelsea, managing only 23 appearances in all competitions for the club.Danny Drinkwater makes his Chelsea debut! 👍 #CHEEVE pic.twitter.com/aGe1HEfpwx— Chelsea FC (@ChelseaFC) October 25, 2017The 30-year-old midfielder's career has had a spectacular nosedive since his heady Leicester days as the 'unwanted' Chelsea player has also found game-time difficult to come by during his loan spells at Burnley and Aston Villa.Drinkwater's lack of professionalism and penchant to be in the headlines for all the wrong reasons (drunk driving, headbutting a teammate, etc.) have largely been his undoing. The player recently spoke about his stint with Chelsea:"I know my Chelsea move hasn’t worked out how anybody would have wanted and I’ve made mistakes, but it’s not as simple as me just not playing football or picking up a wage."The 2015-16 Premier League winner hasn't appeared for Chelsea in more than two years. He was rumoured to leave Chelsea in the summer, but a move did not materialise, and he stayed put in West London.With Drinkwater nowhere near close to breaking into Frank Lampard's first team, a move away from Chelsea could help the player rejuvenate his career when he still has the time to do so.#4 Marcos AlonsoMarcos AlonsoAfter being a key player during his first three seasons at Chelsea, Marcos Alonso has found reduced game-time difficult to come by under Frank Lampard.The 30-year-old, who made over 90 Premier League appearances for the club before Lampard assumed the reins, hasn't played for Chelsea since a calamitous outing in a league game against West Bromwich Albion in September last year.With the excellent Ben Chilwell making the left-back spot his own since his arrival at Chelsea this summer, Marcos Alonso may need to look elsewhere for regular first-team football.Alonso remains a quality player; he has scored the most goals by a defender in the Premier League since the 2016-17 season. However, with the Spain international making three appearances in the competition for Chelsea this season, Alonso is seemingly surplus to requirements at the club.19 - Marcos Alonso has scored 19 goals in the Premier League for Chelsea; the most of any defender in the competition since the start of the 2016-17 season. Resource. pic.twitter.com/pWkWOFm6Ha— OptaJoe (@OptaJoe) February 29, 2020With Chelsea reportedly looking to sell Alonso in January, the player could hope for regular first-team football at another club ahead of the all-important European Championships next summer.