Edmund, playing for the first time since Wimbledon, needed just one hour and nine minutes to win 6-1 6-4.

After saving a break point in the first game, Edmund took Harris' serve in the next and dominated from then on.

However, British number two Dan Evans lost 6-4 6-1 in his first-round match against Japan's Yoshihito Nishioka.

Evans, 29, lost nine of the final 10 games after appearing to struggle in hot conditions which saw temperatures reach 34C.

World number 51 Evans started the match strongly by breaking Nishioka's serve for a 2-0 lead, but could not back it up by holding in the next game.

Nishioka, ranked 77th, broke again for 5-4 and served out the opener, going on to dominate a 27-minute second set.

Edmund will play either France's former Grand Slam semi-finalist Jo-Wilfried Tsonga or Russian world number eight Karen Khachanov in the last 16.

Meanwhile, Heather Watson has gone out of the Silicon Valley Classic in San Jose in the first round, losing 6-3 6-1 in 79 minutes to Zheng Saisai of China.

Elsewhere, fellow Briton Cameron Norrie clinched a second-round spot at the Los Cabos Open in Mexico with a 7-6 (7-5) 6-0 victory over Frenchman Gregoire Barrere.

Dan Evans has climbed back to the brink of the world's top 50 after being without a ranking in April last year following a drugs ban