We have seen many great boxers during the 21st century, but only the best can be named pound-for-pound king each year.
Between the year 2000 and 2021, there have been nine different fighters who have been crowned number one throughout all of the divisions, according to Boxing World Fans that is anyway.
It is the usual suspects who have had that honour and it proves just how lucky we have been to watch them fight.
A post on Instagram has highlighted each of the boxers and there are not many surprises.
At the turn of the century, Shane Mosley was the best in the sport as he was a two-weight world champion at the time after conquering the lightweight and welterweight divisions.
‘Sugar’ later went on to also reign supreme in the light middleweight class to ensure that he was one of the best in the modern era.
Bernard Hopkins was the greatest pound-for-pound boxer in the years 2002 and 2004 with Roy Jones Jr earning the crown in 2003.
Hopkins was the main man in the middleweight division and won all five of his fights between 2002 and 2004.
Jones Jr was a force to be reckoned with and held world titles in four separate weight classes during his career.
Floyd Mayweather does always attract critics, but there is no doubting that he is one of the greatest fighters in history.
Between 2005-2007 and 2012-2014, Floyd revelled in being the pound-for-pound champion and his boxing ability was second to none.
One of the many men that Mayweather beat was Manny Pacquiao, but the PacMan was thought of as being the best fighter on the planet between 2008 and 2011.
The first man in history to win world titles at the four lowest weight classes is Roman Gonzalez and in 2015 and 2016, he was also top of the pound-for-pound rankings.
Gennady Golovkin was one of the most fearsome men on the planet in 2017 until he came face-to-face with Canelo Alvarez. A controversial draw in 2017 was followed by a Canelo victory the year after.
Vasyl Lomachenko then took over in 2018 before the Mexican earned the crown in 2019 through to 2021.