As with all WorldTour races, each team from the top-flight of professional cycling receive an invitation and in the case of the Giro d'Italia, all are contracted to race the first grand tour of the season.
In addition to the WorldTeams, Alpecin-Fenix qualified as the No 1 ranked ProTeam from 2021 while Arkéa-Samsic decided against racing despite qualifying as second best last season, allowing race organisers RCS to hand out three wild card entries to Bardiani-CSF-Faizane, Drone Hopper-Androni Giocattoli and Eolo-Kometa.
Jan Tratnik (Bahrain Victorious) became the first rider to abandon the race after the Slovenian time trial champion was involved in a crash towards the end of the opening stage. Despite completing the following day's time trial, Tratnik who injured his right hand and wrist in the fall, withdrew during the third and final stage in Hungary.
Colombian climber Miguel Ángel López (Astana Qazaqstan), who many had tipped to take a podium spot in Verona, quit during the early part of stage four after suffering with a hip injury, while Jakub Mareczko (Alpecin-Fenix) also bailed.
Filippo Fiorelli (Bardiani-CSF-Faizane) was unable to complete the second stage on his home island, with the 27-year-old leaving the race midway through the fifth day of racing in Sicily.
Michael Morkov (Quick Step-Alpha Vinyl) was unable to start stage seven after Mark Cavendish's lead-out man had developed a fever overnight ahead of the stage in the southern Apennines. Once the stage finally got under way, another three riders – Owain Doull (EF Education-EasyPost), Sergio Samitier (Movistar) and Samuele Zoccarato (Bardiani-CSF-Faizane) also called time on their races.
A second EF Education-EasyPost abandoned the following day when Simon Carr walked during stage eight.
Just one rider failed to complete the final stage before the second rest day, while Rüdiger Selig (Lotto-Soudal) quitting on the road to Blockhaus.
The morning after the night before when Biniam Girmay (Intermarché-Wanty-Gobert Matériaux) made a slice of history by becoming the first black African to win a grand tour stage, the Eritrean was unable to continue having fired a cork into his eye during the podium celebrations.
As expected, Caleb Ewan (Lotto-Soudal) withdrew from the race following stage 11. Ewan was a non-starter the following day as the Australian sprinter switched his focus to the Tour de France where he hopes to endure a better time than he had at the Giro.
There was heartbreak for Romain Bardet (DSM) who abandoned midway through stage 13. The Frenchman who started the stage fourth on general classification and had been looking to be in his best form in years, became ill during the previous day's stage and, according to his team, worsened overnight.
The day after losing their general classification rider Bardet, Cees Bol (DSM) was a non-starter on stage 14, the Dutchman citing fatigue for his reason for quitting the race. Fellow sprinters Giacomo Nizzolo (Israel-Premier Tech) and Alexander Krieger (Alpecin-Fenix) were also absent on the start line. Later in the day, 2017 winner Tom Dumoulin (Jumbo-Visma) abandoned saying he was unable to "pedal away any power without it hurting".
Valerio Conti (Astana Qazaqstan) was unable to complete stage 15 and was forced to abandon "due to a pain in the left leg after his crash a few days ago", according to a statement from his team.
Ecuadorian rider Jonathan Caicedo (EF Education-EasyPost) became the first rider to leave the Giro after testing positive for Covid and did not start stage 16, the 29-year-old's departure becoming the third team-mate of Hugh Carthy's to walk. Later in the day, Natnael Tesfatsion (Drone Hopper-Androni Giocattoli) also got in his team car, the Eritrean calling it a day.
Harm Vanhoucke became the third Lotto-Soudal rider to abandon during stage 17, before later in the day Simon Yates (BikeExchange-Jayco), winner of two stage at this year's race, quit having failed to fully recover from the knee injusry he sustained on the road to Etna during stage four over a fortnight previously.
Fourth on general classification with four stages remaining – and more than likely poised for a podium finish in Verona – Joao Almeida (UAE Team Emirates) abandoned after the Portuguese contracted Covid.
Richie Porte became to first rider from Ineos Grenadiers to abandon when the Australian got off his bike midway through stage 19, citing he had stomach issues. Earlier in the day, Jefferson Cepeda (Drone Hopper-Androni Giocattoli) was the day's only non-starter.
Lilian Calmejane (Fra), Mikaël Cherel (Fra), Felix Gall (Aut), Jaakko Hanninen (Fin), Lawrence Naesen (Bel), Nans Peters (Fra), Nicolas Prodhomme (Fra, neo-pro), Andrea Vendrame (Ita).
Astana Qazaqstan (Kaz)
Joe Dombrowski (US), Fabio Felline (Ita), Vincenzo Nibali (Ita), Vadim Pronskiy (Kaz), Harold Tejada (Col).
Miguel Ángel López (Col, DNF stage four), Valerio Conti (Ita, DNF stage 15), David de la Cruz (Spa, DNF stage 20).
Bahrain Victorious (Brn)
Phil Bauhaus (Ger), Pello Bilbao (Spa), Santiago Buitrago (Col), Mikel Landa (Spa), Domen Novak (Slo), Wout Poels (Hol), Jasha Sütterlin (Ger).
Jan Tratnik (Slo, DNF stage three).
Lawson Craddock (US), Lucas Hamilton (Aus), Michael Hepburn (Aus), Damien Howson (Aus), Christopher Juul-Jensen (Den), Callum Scotson (Aus), Matteo Sobrero (Ita).
Simon Yates (GB, DNF stage 17).
Giovanni Aleotti (Ita, neo-pro), Cesare Benedetti (Pol), Emanuel Buchmann (Ger), Patrick Gamper (Aut), Jai Hindley (Aus), Lennard Kämna (Ger), Wilco Kelderman (Hol), Ben Zwiehoff (Ger).
Davide Cimolai (Ita), Simone Consonni (Ita), Wesley Kreder (Ned), Guillaume Martin (Fra), Anthony Perez (Fra), Pierre-Luc Périchon (Fra), Rémy Rochas (Fra), Davide Villella (Ita).
Thymen Arensman (Ned, neo-pro), Romain Combaud (Fra), Alberto Dainese (Ita, neo-pro), Nico Denz (Ger), Chris Hamilton (Aus), Martijn Tusveld (Ned).
Romain Bardet (Fra, DNF stage 13), Cees Bol (Ned, DNS stage 14).
EF Education-EasyPost (US)
Diego Camargo (Col, neo-pro), Hugh Carthy (GB), Magnus Cort (Den), Merhawi Kudus (Eri), Julius van den Berg (Ned).
Owain Doull (GB, DNF stage seven), Simon Carr (GB, neo-pro; DNS stage eight), Jonathan Caicedo (Ecu, DNS stage 16).
Clément Davy (Fra, neo-pro), Arnaud Démare (Fra), Jacopo Guarnieri (Ita), Ignatas Konovalovas (Ltu), Tobias Ludvigsson (Swe), Miles Scotson (Aus), Ramon Sinkeldam (Ned), Attila Valter (Hun).
Ineos Grenadiers (GB)
Richard Carapaz (Ecu), Jonathan Castroviejo (Spa), Jhonatan Narváez (Col), Salvatore Puccio (Ita), Pavel Sivakov (Fra), Ben Swift (GB), Ben Tulett (GB).
Richie Porte (Aus, DNF stage 19).
Intermarché-Wanty-Gobert Matériaux (Bel)
Aimé De Gendt (Bel), Jan Hirt (Cze), Barnabas Peak (Hun), Domenico Pozzovivo (Ita), Lorenzo Rota (Ita), Rein Taaramae (Est), Loïc Vliegen (Bel).
Biniam Girmay (Eri, DNS stage 11).
Israel-Premier Tech (Isr)
Jenthe Biermans (Bel), Matthias Brändle (Aut), Alexander Cataford (Can), Alessandro De Marchi (Ita), Alex Dowsett (GB), Reto Hollenstein (Swi), Rick Zabel (Ger).
Giacomo Nizzolo (Ita, DNS stage 14).
Edoardo Affini (Ita), Koen Bouwman (Ned), Pascal Eenkhoorn (Ned), Tobias Foss (Nor), Gijs Leemreize (Ned, neo-pro), Sam Oomen (Ned), Jos van Emden (Ned).
Tom Dumoulin (Ned, DNF stage 14).
Thomas De Gendt (Bel), Matthew Holmes (GB), Roger Kluge (Ger), Sylvain Moniquet (Bel, neo-pro), Michael Schwarzmann (Ger).
Rüdiger Selig (Ger, DNF stage nine), Caleb Ewan (Aus, DNS stage 12), Harm Vanhoucke (Bel, DNF stage 17).
Jorge Arcas (Spa), Will Barta (US), Oier Lazkano (Spa), Antonio Pedrero (Spa), José Joaquín Rojas (Spa), Iván Sosa (Col), Alejandro Valverde (Spa).
Sergio Samitier (Spa, DNF stage seven).
Quick Step-Alpha Vinyl (Bel)
Davide Ballerini (Ita), Mark Cavendish (GB), James Knox (GB), Mauro Schmid (Swi, neo-pro), Pieter Serry (Bel), Bert Van Lerberghe (Bel), Mauri Vansevenant (Bel, neo-pro).
Michael Morkov (Den, DNS stage seven).
Dario Cataldo (Ita), Giulio Ciccone (Ita), Juan Pedro López (Spa), Bauke Mollema (Hol), Jacopo Mosca (Ita), Mattias Skjelmose Jensen (Den, neo-pro), Edward Theuns (Bel), Otto Vergaerde (Bel).
UAE Team Emirates (UAE)
Rui Costa (Por), Alessandro Covi (Ita), Davide Formolo (Ita), Fernando Gaviria (Col), Rui Oliveira (Por), Maximiliano Richeze (Arg), Diego Ulissi (Ita).
Joao Almeida (Por, DNS stage 18).
Tobias Bayer (Aut), Dries De Bondt (Bel), Senne Leysen (Bel), Stefano Oldani (Ita), Oscar Riesebeek (Ned), Mathieu van der Poel (Ned).
Jakub Mareczko (Ita, DNF stage four), Alexander Krieger (Ger, DNS stage 14).
Luca Covili (Ita), Davide Gabburo (Ita), Sacha Modolo (Ita), Luca Rastelli (Ita), Alessandro Tonelli (Ita), Filippo Zana (Ita).
Filippo Fiorelli (Ita, DNF stage five), Samuele Zoccarato (Ita, DNF stage seven).
Drone Hopper-Androni Giocattoli (Ita)
Mattia Bais (Ita), Andrii Ponomar (Ukr), Simone Ravanelli (Ita), Eduardo Sepúlveda (Arg), Filippo Tagliani (Ita), Edoardo Zardini (Ita).
Natnael Tesfatsion (Eri, DNF stage 16), Jefferson Cepeda (Ecu, DNS stage 19).
Vincenzo Albanese (Ita), Davide Bais (Ita), Erik Fetter (Hun), Lorenzo Fortunato (Ita), Francesco Gavazzi (Ita), Mirco Maestri (Ita), Samuele Rivi (Ita), Diego Rosa (Ita).
DNF: Did not finish; DNS: Did not start; DSQ: Disqualified; OTL: Outside time limit