In 2021, we have learnt that you should only ever focus on one fight at a time.
There were plans for an all-British unification between Anthony Joshua and Tyson Fury, Teofimo Lopez to move up and face Josh Taylor and Kid Galahad to unify the featherweight division in 2022.
All of these were scuppered by huge upsets in the ring. Planet Sport has taken a look at seven fights that shook the boxing fraternity in 2021.
Mexico haunts Matchroom again
Josh Warrington down twice as Mauricio Lara stops him behind closed doors (February 13, 2021)
As a result of the Covid-19, 'The Leeds Warrior' had taken a year and four months out of the ring up until this fight. In this time, he had split with Frank Warren's Queensberry Promotions and re-joined Eddie Hearn's Matchroom Boxing.
The fight with Lara was his first bout with Matchroom since 2016. It was seen as a safe return fight as his Mexican opponent was a relative nobody before this.
Warrington usually sets the pace in his fights, but he started slowly against Lara in unfamiliar surroundings behind closed doors.
His young opponent grew in confidence and dropped Warrington with a vicious left hook in the fourth. The Brit returned to his feet but he never recovered and it proved to be the worst night of his professional career.
Lara was a major underdog going in but the upset was complete in the ninth, as a brave Warrington was knocked down for a second time.
The rivals rematched in July in front of 20,000 at Headingley Stadium, Leeds. Warrington was unable to get his revenge as the bout ended as a premature draw after Lara suffered a severe cut following a head clash.
Icon retires from boxing
Manny Pacquiao outpointed by Yordenis Ugas (21 August 2021)
Before this fight, the Filipino legend had already achieved just about everything as a boxer. He had won world titles in eight weight classes and was rightly regarded as one of the greatest of all-time.
Pacquiao became a world champion again in 2019 when he defied the odds to outpoint Keith Thurman to snare away his WBA (Super) welterweight title.
Pacman, 42 at the time, had to vacate the belt due to inactivity, but he once again challenged for it again in his 72nd professional fight against Ugas.
He was initially due to fight Errol Spence Jr, but 'The Truth' had to pull out as he suffered an eye injury. Ugas was seen as a weaker opponent than Spence and Pacquiao was favoured to come out on top.
Sadly, Pacquiao was nowhere near his best against the Cuban as it appeared father time had caught up with him. Ugas triumphed via unanimous decision and is now due to face IBF and WBC champion Spence in a unification bout in 2022. It leaves Terence Crawford unsure of his next fight...
Oleksandr Usyk batters Anthony Joshua to become two-weight world champion (September 25, 2021)
The first part of 2021 was dominated by talks between the camps of Joshua and Tyson Fury. An all-British unification bout looked set for Saudi Arabia until an arbitration case involving Deontay Wilder ruined those plans.
Instead, Fury was made to fight Wilder for the third time, while Joshua battled Usyk - his WBO mandatory challenger.
'The Gypsy King' won again in what was a heavyweight barnstormer against Wilder, ending in round 11 via KO.
The same can't be said for AJ, though. While Usyk was acknowledged as a modern-day great, there were still doubts surrounding him at heavyweight.
After his impressive showing against Kubrat Pulev last time out, many believed AJ's size and power would be too much for his skilled opponent.
This was not the case on the night as Joshua made the foolish mistake of attempting to outbox the boxer. He was schooled and even hurt by Usyk, who won comprehensively on the cards.
A rematch looks set to happen in March or April and it now would be classed as a shock if Joshua won. Boxing is a funny old sport…
Garcia stunned in Fresno
Spaniard Sandor Martin gets the decision against four-division world champion Mikey Garcia (October 16, 2021)
Garcia - who had previously beaten the likes of Juan Manuel Lopez, Adrien Broner and Jessie Vargas - is a four-weight world champion.
The only loss of his career had come in 2019 against Spence Jr. Earlier this year, he stepped in with Martin, who was making a name for himself as part of Matchroom's Spanish branch.
Martin was not considered to be on the same level as Garcia heading into the fight having never fought outside of his native in a 41-fight career.
2021 was a theme for higher calibre fighters not taking an opponent seriously enough and Garcia continued the trend by being outfought and outworked by Martin.
Martin picked up the biggest victory of his career to date as he bested Garcia on the cards as he won via unanimous decision. He is now targeting world title honours at welterweight.
A star is born!
Alycia Baumgardner beats unbeaten Terri Harper (November 13, 2021)
Now onto the first of two entries from November's card at the Sheffield Arena. Harper's return to the ring after a year lay-off was the chief support on the night.
The Doncaster-born super featherweight was set to fight Hyun Mi Choi in May, but a hand injury in sparring forced that clash to be cancelled. Harper was fit to return in November and she defended her WBC and IBO world titles against Alycia Baumgardner.
The American relished the villain role she found herself in as she put in a career-making performance against the champion. She was on top heading into the fourth round and her crowning moment came at the start of that round.
Baumgardner caught Harper with a lethal right hand that left the latter standing static in the middle of the ring. The referee recognised that Harper was out of it as he called time on the contest.
The Brit has since made her intentions known to step up to lightweight - a division currently dominated by Katie Taylor. Harper's defeat was a huge shock, but an even bigger surprise was to come in the main event...
Kiko Martinez rolls back the years
Martinez KOs hometown boy Kid Galahad (November 13, 2021)
Topping the bill was Galahad, who was making the first defence of his IBF world featherweight title.
He picked up that belt in August after a one-sided win over his fellow Brit Jazza Dickens. Galahad had become world champion in his second attempt having lost out to Josh Warrington in 2019.
Galahad put his title on the line against Spanish veteran Martinez. His opponent had previously been the IBF super bantamweight champion between 2013 and 2014.
The 35-year-old was considered a durable first challenger, who did not really stand a chance of ousting the champion.
Up until the end of round five, the bout stuck to the script. Galahad was boxing well; he established his jab early on and he had clearly won every round.
The fight was turned on its head in the closing moments of round five, however. Galahad got decked inside the final 20 seconds by an overhand right hook.
The hometown fighter looked shell shocked as he returned to his feet but he was saved by the bell at the end of the round. Looking back, Galahad may have wished it ended there as just seconds into the sixth, he was dropped again by another flush right hand.
This time the fight was waved off and Spain had themselves a new world champion.
Lopez stunned in New York
George Kambosos Jr snatches away Teofimo Lopez's belts (November 27, 2021)
The lightweight division is arguably the most exciting weight class in men's boxing coming out of 2021. The likes of Devin Haney, Gervonta Davis and Vasiliy Lomachenko are all vying to be number one.
Lopez and Kambosos Jr had the chance to stake their claim when they faced off in New York last month.
The long-awaited fight was for Lopez's WBA (Super), IBF, WBO and The Ring world titles. He pulled off one of 2020's biggest shocks after handing Lomachenko his first loss at lightweight to take the belts.
This victory placed Lopez atop the division, with many considering him to be the best of the bunch. His first defence of the belts was against Kambosos - his IBF mandatory challenger.
The Australian was deemed as a credible challenger but a deal had reportedly been agreed for Lopez to face Haney for all of the belts next - as long as he beat Kambosos.
There were also reports that Lopez was preparing to fight Josh Taylor in a bid to become a two-division world champion at 140lbs.
However, Kambosos ripped up the script and prevailed as the underdog to become the new king of the lightweight division.
In what proved to be a Fight of the Year contender, the challenger downed Lopez in the first. The 24-year-old scored a knockdown of his own in the tenth although it went the full distance.
Kambosos was widely considered to be the worthy winner and the judges scored it a split-decision win in his favour.
Lopez's journey at lightweight appears to be over, while Kambosos is looking to unify the division in 2022 as a fight against WBC champion Haney is possible.
2021 has been a good year for boxing, but 2022 may well top it and there will no doubt be more shock results along the way…