2020 All-Ireland Senior Football Championship

The 2020 All-Ireland Senior Football Championship was the 133rd edition of the Gaelic Athletic Association's premier inter-county Gaelic football tournament since its establishment in 1887.
The public health measures introduced to combat the COVID-19 pandemic resulted in the competition being delayed. On 17 March, the GAA confirmed that the opening fixture – due to have taken place at Gaelic Park in The Bronx on 3 May – had been postponed. In June, the GAA announced that the 2020 championship would be straight knock-out, the first straight-knockout since 2000.
Thirty teams took part – thirty of the thirty-two counties of Ireland. New York were unable to participate due to travel restrictions resulting from the COVID-19 pandemic. London will play no part in the 2020 All-Ireland championships after a meeting of the GAA's Ard Chomhairle on 12 September 2020. Sligo withdrew also due to a COVID-19 outbreak from 3 November.
London were initially scheduled to host Roscommon at Ruislip at the beginning of May, before all GAA activity was postponed due to the COVID-19 pandemic. Michael Maher's team were then set to play their rescheduled Connacht football quarter-final on the weekend of 31 October, with the winner facing Mayo or Leitrim the following weekend. Roscommon advanced directly into the semi-final.
The Galway vs Sligo Connacht semi-final was not played as Sligo were affected by COVID-19 cases. Galway's first match was the Connacht final and the Connacht championship only had four teams instead of the usual seven. It happened before Galway to qualify for Connacht final without playing any matches during the period that all Connacht finals were between Galway and Mayo (1933-1940).
It emerged that in order for London's quarter-final to take place their entire squad and backroom team would have to self-isolate in Ireland for two weeks prior to the match. Kilkenny, as in previous years, did not enter.
Galway were winners over Sligo. Sligo are back in 2021 but London and New York games litely to rescheduled for 2022. 
Initially the GAA intended to introduce the Tailteann Cup, a second-tier championship for Division 3 and 4 National Football League teams who failed to reach their provincial finals or get promoted to Division 2 of the league. The Tailteann Cup was cancelled as a result of the impact of the COVID-19 pandemic on Gaelic games and was rescheduled for introduction in 2021, when its introduction was again postponed.
Defending champions Dublin completed an unprecedented six-in-a-row.
Competition format.
Provincial Championships format.
Connacht, Leinster, Munster and Ulster each organise a provincial championship. Most of the teams who lost a match in their provincial championship entered the All-Ireland qualifiers in the years prior to 2020 – New York did not enter the qualifiers. As the championship was delayed due to the impact of the COVID-19 pandemic, the qualifiers were abandoned with all matches being changed to straight knock-out.
If the score is level at the end of the normal seventy minutes, two periods of ten minutes each way are played. If the score is still level the tie is decided by a penalty shoot-out.
All-Ireland format.
The four provincial champions compete in the semi-finals. If the score is level at the end of the normal seventy minutes in a semi-final, two periods of ten minutes each way are played. If the score is still level the semi-final is replayed. If the score is level at the end of the normal seventy minutes in the final, the match is replayed.
Rule changes from 2019 competition.
Initially trialled in the 2019 Leagues, the advanced mark rule was introduced in 2020. The possibility of an advanced mark occurs when a player catches a ball cleanly on or inside a 45m line from a kick in play delivered by an attacking player on or beyond the opposition's 45m line that travels at least 20m and without touching the ground. The player who catches the ball, either an attacker or defender, can signal his intent to stop and take the free-kick resulting from the mark by raising an arm or play on immediately.
A player who commits a black card offence is sent off the pitch to the sin-bin for ten minutes. Teams are not permitted to replace the player while he is in the sin-bin. If a player commits another black card offence or a yellow card offence after returning to the field he is also given a red card.
Goalkeepers must take their kick-out from the 20 metre line (previously kick-outs were taken from the 13 metre line). The ball must be kicked forward and all players must be 13 metres from the ball until it has been kicked.
Following a motion proposed by Kildare at the GAA Congress on 28 September 2020, the kick-out rule was further modified so that an outfield player receiving a ball direct from the kick-out cannot play the ball back to their goalkeeper. Unusually, the "no back-pass" modification was not trialled before its introduction in the 2020 senior championship.
Provincial championships.
Munster Senior Football Championship.
The two teams who won the semi-finals in the previous year are given byes to this year's semi-finals.
Ulster Senior Football Championship.
An un-seeded draw determined the fixtures for all nine teams. In April 2018, the Ulster GAA Competitions Control Committee introduced a rule that the two teams who play in the preliminary round are exempt from playing in the preliminary round in the following two years. As a result of the draw for 2020, Cavan and Monaghan are awarded byes to the quarter-finals in 2021 and 2022.
Awards.
 Player has previously been selected.