Chelsea fans were impressed by Marcos Alonso's performance for Spain in their UEFA Nations League victory over Italy on Wednesday. Many of them labeled the defender as the best left-back in the world at the moment.Marcos Alonso enjoyed a great start to the 2021-22 season. His good performances for Chelsea saw him get selected for Spain's squad ahead of the international break. The 30-year-old put in an amazing display in Spain's Nations League semi-final win over Italy. His side beat the Euro 2020 winners 2-1, courtesy of a brace from Manchester City attacker Ferran Torres.It was only the full-back's fourth cap for Spain, prompting Chelsea fans on Twitter to rave about his performance even more. Here are some of the best tweets about him:Yimzy🇸🇪@YimzyAgainMarcos Alonso- UEFA Champions League Winner- UEFA Super Cup winner- UEFA Nations League FinalistA New Ballon D’or Charge??2:15 AM · Oct 7, 20212015231Marcos Alonso- UEFA Champions League Winner- UEFA Super Cup winner- UEFA Nations League FinalistA New Ballon D’or Charge?? https://t.co/qmCBqZu6coAndy Darks@abi_darksThe best LB in the world right now…Marcos Alonso2:17 AM · Oct 7, 202137326The best LB in the world right now…Marcos Alonso https://t.co/bxvt64MhuVWAGNH@WAGNH_CFCTurns out what was needed to stop Italy’s record unbeaten streak was Marcos Alonso#CFC weaintgotnohistory.sbnation.com/2021/10/7/2271…9:15 AM · Oct 7, 2021271Turns out what was needed to stop Italy’s record unbeaten streak was Marcos Alonso#CFC weaintgotnohistory.sbnation.com/2021/10/7/2271…🤥@zak_a15Marcos Alonso is so clean what a player5:24 AM · Oct 7, 2021Marcos Alonso is so clean what a playerWirjil@WirjilMarcos Alonso is the best Left-back in the world atm don’t @ me. #CFC #ITAESP4:30 AM · Oct 7, 2021177Marcos Alonso is the best Left-back in the world atm don’t @ me. #CFC #ITAESP https://t.co/R9Sy4w6BS4Eshan Pokhrel@EshanPokhrelmarcos alonso>>> luke shaw sorry brits4:05 AM · Oct 7, 20211marcos alonso>>> luke shaw sorry britsMr B@BulusSimon1Marcos Alonso any day anytime never in doubt, lampard tried to destroy him but God was on his side💙Marcos Alonso the great#ItalySpain3:43 AM · Oct 7, 20211Marcos Alonso any day anytime never in doubt, lampard tried to destroy him but God was on his side💙Marcos Alonso the great#ItalySpainChessy Hour® ☆☆@ChessyHourAlonso is inevitable nan. He was excellent yesterday with his passing and he fully made Spain’s left hand side so dangerous. Italy couldn’t cope with that extra body in Spain’s offensive 3rd. - Meeds12:39 PM · Oct 7, 202161Alonso is inevitable nan. He was excellent yesterday with his passing and he fully made Spain’s left hand side so dangerous. Italy couldn’t cope with that extra body in Spain’s offensive 3rd. - MeedsSimon Peter Wanyama@spwanyama@CFCDaily Spain will win the trophy with Azpi and Alonso9:00 AM · Oct 7, 20211@CFCDaily Spain will win the trophy with Azpi and Alonsobig sheq.@petrshekGood game for Alonso at left back against Italy? this guy never fails to surprise me.10:49 AM · Oct 7, 20212Good game for Alonso at left back against Italy? this guy never fails to surprise me.⭐rmundin⭐@rMundinCFCMarcos Alonso best LB in the world in my books1:10 AM · Oct 7, 20214Marcos Alonso best LB in the world in my booksgerald@davidinho_21Alonso balled at lb today3:12 AM · Oct 7, 20212Alonso balled at lb todayMarcos Alonso has been a vital member of the Chelsea squad ever since Thomas Tuchel took over from Frank Lampard. The Spaniard thrives in a back-five system where he plays as a left wing-back.Alonso was instrumental for Chelsea when Antonio Conte was their manager from 2016 to 2018. The Italian manager played a similar back-five system to Thomas Tuchel.Marcos Alonso has made six Premier League appearances for Chelsea so far this season. He has already registered a goal and an assist.The Blues now have two in-form left-backs in their squad after Ben Chilwell returned to Premier League action over the weekend. He scored a goal against Southampton in a 3-1 win for his side.Chelsea recovered from a slight hiccup to top the Premier League before the international breakGoing into the international break, Chelsea found themselves at the top of the Premier League charts following their win over Southampton.The Blues recovered well after suffering two defeats on the bounce. First, they were outplayed by Manchester City in the Premier League and were defeated 1-0. They then suffered a 1-0 loss to Serie A giants Juventus in the Champions League. Chelsea are one point ahead of Liverpool on the Premier League table and two points clear of both Manchester clubs.Goal@goalThe Premier League table is TIGHT heading into the international break 😅12:42 PM · Oct 4, 2021138531087The Premier League table is TIGHT heading into the international break 😅 https://t.co/YWLu9suJPQAfter the international break, Chelsea will travel to face Brentford, who are coming off a 2-1 win over West Ham. The newly promoted side have stunned quite a few teams in the Premier League with their great style of play.Brentford defeated Arsenal on the opening day of the Premier League before holding off Liverpool in an exciting 3-3 draw.