Late in 1189, Armengol de Aspa abdicated and a new Grand Master was not chosen until Garnier of Nablus was elected in 1190. Garnier had been seriously injured at Hattin in 1187, but managed to reach Ascalon and recovered from his wounds. He was in Paris through that time waiting for Richard I of England to depart on the Third Crusade. He arrived in Messina on 23 September where he met Philippe Auguste and Robert IV de Sablé, soon to be Grand Master of the Templars.

Garnier left Messina on 10 April 1191 with Richard's fleet, which then anchored on 1 May at the port of Lemesos. Richard subdued the island on 11 May despite the mediation of Garnier. They set sail again on 5 June and arrived in Acre, under Ayyubid control since 1187. There they found Philippe Auguste leading the Siege of Acre, a two-year attempt to dislodge the Muslims. The besiegers eventually got the upper hand and, under the helpless eyes of Saladin, the Muslim defenders capitulated on 12 July 1191.

On 22 August 1191, Richard travelled south to Arsuf. The Templars formed the vanguard and the Hospitallers at the rear-guard. Richard travelled with an elite force ready to intervene where necessary. The Hospitallers came under attack on September 7, at the beginning of the Battle of Arsuf. Situated at the rear of the military column, Garnier's knights were under heavy pressure by the Muslims and he rode forward to persuade Richard to attack, which he refused. Finally, Garnier and another knight charged forward, and were soon joined by the rest of the Hospitaller force. Richard, despite the fact that his orders had been disobeyed, signaled for a full charge. This caught the enemy at a vulnerable moment, and their ranks were broken. Garnier thus played a large part in winning the battle, though in contravention of Richard's orders.