Ridden as on his debut by Robert Havlin he led for most of the way and rallied after being headed in the closing stages to win in a blanket finish from Bowerman, Mutarabby and Lethal Impact.

Over ten furlongs Beverley Racecourse on 19 April he carried a weight of 131 pounds and won "readily" by six lengths from Election Day.

At Royal Ascot on 23 June, the colt was stepped up in class and distance to contest the Group 2 Queen's Vase over 14 furlongs in which he was partnered by Andrea Atzeni.

Starting the 11/2 second choice in the betting he overcame interference in the straight to take the lead inside the final furlong and on by a neck from Count Octave.

Ridden by Atzeni he started the 6/1 second favourite behind Big Orange (winner of the race for the last two years) while the other runners included US Army Ranger, Wicklow Brave (Irish St Leger), Sheikhzayedroad (Northern Dancer Turf Stakes), Pallasator (Doncaster Cup), Qewy (Geelong Cup), Higher Power (Northumberland Plate), High Jinx (Prix du Cadran) and Sweet Selection (Cesarewitch).

[9] He made steady progress on the inside in the straight and finished third, beaten half a length and a short head by Capri and Crystal Ocean with Rekindling in fourth.

[10] On his final start of the year he took on older horses again the British Champions Long Distance Cup over two miles at Ascot in October in which he finished third behind Order of St George and Torcedor, beaten a length by the winner.

"[15] On 31 July Stradivarius attempted to repeat his 2017 success in the Goodwood Cup and started 4/5 favourite against six opponents headed by Torcedor, Idaho and Desert Skyline.

He won the race and earned the £1 million bonus, beating Count Octave by one and a half lengths after taking the lead a furlong out.

[18] Stradivarius ended his season in the Group 2 British Champions Long Distance Cup at Ascot on 20 October although Gosden had considered withdrawing him on account of the soft ground.

He started favourite again, with the best-fancied of his five rivals being the Aidan O'Brien-trained three-year-olds Flag of Honour (winner of the Irish St Leger) and Sir Erec.

Approaching the final turn he was boxed in on the rail and looked unlikely to get a clear run but Dettori found a gap on the inside and sent him to the front two furlongs out.

[22] Stradivarius began his fourth campaign with an attempt to repeat his 2018 success in the Yorkshire Cup and started at odds of 4/5 against seven opponents including Ispolini (Nad Al Sheba Trophy), Southern France (Yeats Stakes), Mildenberger (Feilden Stakes) Sevenna Star (Sandown Classic Trial) and Desert Skyline.

"[24] On 20 June Stradivarius ran for the second time in the Ascot Gold Cup and started favourite despite Gosden's concerns that he would be unsuited by the soft ground.

Dee Ex Bee and Cross Counter renewed their opposition, while the best fancied of the other five runners was the three-year-old Dashing Willoughby (Queen's Vase).

His success made him the seventh horse after Isonomy, Alycidon, Souepi, Le Moss, Longboat and Double Trigger to win the Stayers' Triple Crown.

[30] On 19 October Stradivarius attempted to win his eleventh consecutive race as he ran for the third time in the British Champions Long Distance Cup and went off the 8/13 favourite.

The closing stages saw Stradivarius and the four-year-old Kew Gardens draw away from the field and although the favourite gained a narrow lead a furlong out, his younger rival rallied in the final strides to win by a nose.

[34] At Royal Ascot on 18 June Stradivarius attempted to become the third horse after Sagaro and Yeats to win a third consecutive Ascot Gold Cup and was made the 4/5 favourite ahead of seven opponents including Technician, Cross Counter, Moonlight Spirit (Prix de Lutèce), Nayef Road (Sagaro Stakes), Prince of Arran (Geelong Cup) and Withhold (Northumberland Plate).

Dettori settled the favourite in mid-division as Nayef Road set the pace and then made steady progress on the outside as the field entered the straight.

[35] On 28 July, despite giving substantial weight (15 lbs) to the younger horse Santiago and getting boxed in before the final run to victory, Stradivarius won a record fourth Goodwood Cup by one length.

Starting favourite at odds of 5/6, he was denied a clear run turning into the home straight and finished in fourth position over seven lengths behind the winner Subjectivist.

[38] Gosden announced that Stradivarius would stay in training for a final season in 2022, with another attempt at winning a fourth Ascot Gold Cup.

He missed the Lonsdale Cup on account of a bruised foot and in September 2022 it was announced that he would be retired to stand at the National Stud in Newmarket.

He stood at a modest fee of £10,000, as stamina is not as popular as speed in flat stallions, and breeders were offered bonuses for producing winning progeny.