Stan Wawrinka breezed past Cameron Norrie and top seed Marin Cilic also eased to a straight-sets victory over Fernando Verdasco in the first round of the Fever-Tree Championships on Monday.
Wawrinka was beaten in the first round of the French Open as he eases his way back from two knee operations, but won his first game of the grass-court season 6-2 6-3 in just 56 minutes.
The three-time grand slam champion hit 13 aces and lost only four of his first-service points in an emphatic win over the British wildcard on day one at Queen's Club.
Wawrinka, a semi-finalist in this event four years ago, broke five times and did not face a solitary break point as he set up a meeting with fifth seed Sam Querrey.
Cilic was too good for Verdasco in his first match since losing to Juan Martin del Potro in the quarter-finals of the French Open, winning 6-3 6-4.
The 2012 champion lost just four service points and broke three times to power his way past Spaniard Verdasco and will now face Gilles Muller, who beat Denis Shapovalov 7-6 (9-7) 7-6 (8-6).
Querrey got past another British wildcard, Jay Clarke, while Daniil Medvedev ousted sixth seed Jack Sock 7-5 6-3 and Frances Tiafoe was another first-round winner.