Modern football has seen attacking tridents become the norm. Managers expect fluidity in attack, with forwards capable of interchanging positions to cause maximum damage.This has resulted in some of the best attacking sides in football. It helps when one of your attackers is either Lionel Messi or Cristiano Ronaldo, two of the best footballers to have played the game.Barcelona and Real Madrid's dominance is clear. The two La Liga giants were feared in the early 2010s, with some of the best players in the world playing for the sides.On that note, we look at the 5 highest scoring trios of the 21st century.Note: All stats were gathered from transfermarkt.com#5 Lionel Messi (73), Cesc Fabregas (15) and Xavi (14) | Barcelona | 2011/12Lionel Messi and Xavi are regarded as legends of BarcelonaPep Guardiola's final season as Barcelona manager saw Lionel Messi go haywire, as the superstar forward scored 73 goals in all competitions for the club.Barcelona endured a quiet season, finishing 2nd in La Liga behind Jose Mourinho's Real Madrid. The Catalan club were knocked out of the UEFA Champions League by Chelsea in the semi-finals, as Guardiola bowed out after enjoying incredible success as manager of the club.60 games73 goals31 assistsEight years since Leo Messi scored the final goal of his record-breaking 2011/12 season 🤯 pic.twitter.com/mn5uZzauwi— B/R Football (@brfootball) May 25, 2020Cesc Fabregas, who returned to Barcelona in 2011 for a fee of £30.5 million, scored 15 goals in all competitions for the club but never truly fit in at Barcelona, as he joined Chelsea in 2014.Legendary midfielder Xavi, not renowned for his goalscoring, recorded 14 goals that season, scoring 10 goals in the league. This was the first and only time Xavi reached double figures for goals in La Liga.#4 Lionel Messi (54), Luis Suarez (36) and Neymar (20) | Barcelona | 2016/17Lionel Messi, Neymar and Luis Suarez were a fearsome trioLike Pep Guardiola before him, Barcelona manager Luis Enrique announced in March 2017 that the 2016/17 season was going to be his final season as Barcelona boss.The Spaniard enjoyed a decorated spell as Barcelona manager and won the treble in 2015. Much of that success was down to their three forwards, as Lionel Messi, Luis Suarez and Neymar proved to be a fearsome trio and are regarded as one of the best attacking tridents in football history.Luis Suarez for Barcelona 🔵🔴📆 2014-15⚽️ 25 goals🅰️ 23 assists📆 2015-16⚽️ 59 goals🅰️ 24 assists📆 2016-17⚽️ 37 goals🅰️ 18 assists📆 2017-18⚽️ 31 goals🅰️ 19 assists📆 2018-19⚽️ 25 goals🅰️ 13 assists📆 2019-20⚽️ 21 goals🅰️ 12 assists pic.twitter.com/Evh7QaeHmI— Goal (@goal) September 24, 2020The 2016/17 season was not trophy-laden for the Camp Nou outfit. Despite their frontline being in fine form, Barcelona finished 2nd in La Liga, behind Zinedine Zidane's Real Madrid. They were knocked out of the UEFA Champions League by Juventus in the quarter-finals.Barcelona fans will remember this season because of La Remontada. The Catalans overcame a 4-0 deficit in the first-leg against Paris Saint-Germain in the Round of 16 of the UEFA Champions League to beat them 6-1 in the second leg and progress to the next round.Also Read: 5 wonderkids who have not lived up to the hype this season