Josh Maja, Jeremain Lens and Billy Jones were on the scoresheet as Sunderland beat Bradford City 3-2 in their latest friendly.
Sunderland raced into an early two goal lead against their League One counterparts with Josh Maja and Jeremain Lens again netting, Maja's fourth of pre-season.
Jones added a third from close range as Sunderland went in 3-0 up at the break after their best performance of pre-season to date.
Substitutions disrupted Sunderland's rhythm second half as Bradford fought back and Sunderland had trialist Robbin Ruiter in goal to thank for ensuring victory.
The stopper had a busy second half, including a superb point blank save late on to help Sunderland to victory.
With only three remaining friendlies before the opening game of the Championship season, Grayson named a strong side at the Northern Commercials Stadium at Valley Parade.
Ruiter, who has been training with the club following the sale of Vito Mannone to Reading for £2million, started.
Ruiter, previously linked with Dutch giants PSV Eindhoven and Ajax, is a free agent after leaving FC Utrecht at the end of the season.
The 6ft 5in shot-stopper arrived on Wearside aiming to prove his fitness after spending a long spell on the sidelines last season with a fractured collarbone.
Brendan Galloway (calf) and Jack Rodwell (dead leg) missed out again, while Aiden McGeady is still building his fitness.
Sunderland made a storming start, quickly going 2-0 up within eight minutes - Lens at the heart of the action.
Donald Love played Lens in down the right wing five minutes in, the Dutch winger set himself before whipping in a pin-point cross to Maja, the in-form striker coolly slotting home from six-
Three minutes later Sunderland had doubled their lead thanks to a sublime finish solo effort from Lens.
It was poor from the Bradford defence but a fine effort from Lens as he evaded two challenges before checking back onto his left foot and chipping the keeper.
Didier Ndong tried his luck 21 minutes in, his effort from the edge of the area deflected over for a Sunderland corner with the Black Cats dominating.
Ruiter had little to do initially but when called into action produced a smart block to deny Shay McCartan after he had burst into the box, the stopper spreading himself well in the 28th minute.
Ndong , again from distance, chanced his arm but Rouven Sattelmaier dived to his right to make a comfortable save.
The Gabon international was at the heart of Sunderland's play and the third goal came from his 42nd minute shot, which was parried by Sattelmaier to Jones who bundled home.
Bradford, who had failed to properly defend the corner, looked suspect at the back but Sunderland were clinical.
Ruiter ended the half with another smart, low save from Adam Chicksen.
Half-time: Bradford 0 Sunderland 3
There were no subs at the break but Maja - who again impressed - was taken off within five minutes of the restart, Joel Asoro on in his place. Maja looked to have suffered a knock.
Sunderland continued where they left off in the first half with Lens again dangerous down the right flank and Ndong seeing another shot blocked.
Vaughan saw a header from a Khazri free-kick go over the bar before a fierce effort from 25-yards on the hour mark was comfortably held by Sattelmaier.
Lens appealed for a penalty after going down under pressure form Chicksen - who he had given a torrid time - but referee Geoff Eltringham waved away the appeals.
Bradford pulled a goal back in the 65th minute, Ndong judged to have fouled McCartan inside the area and Tony McMahon sent Ruiter the wrong way from the spot.
With their confidence boosted, League One Bradford pushed further forward with Sunderland getting deeper and deeper, McCartan dictating play for the hosts.
Bantams sub Paul Taylor was close to scoring having easily beaten Tyias Browning in the area, Ruiter again out quickly to make an impressive block in the 79th minute.
Ruiter was enjoying a far busier second half and made a brilliant point-blank save in the closing stages of the game to maintain Sunderland's lead.
He will have done his chances of earning a deal no harm with an assured display.
Bradford scored again right at the death, trialist Jordan Gibson sweeping home the ball from close range at the front post to cut the deficit.
Sunderland were excellent first half but dropped off second half and allowed Bradford back into the game.
Sunderland face Scunthorpe United away on Wednesday night before the showpiece friendly with Celtic next Saturday at the Stadium of Light.
Full-time: Bradford 2 Sunderland 3
Sunderland (4-4-2): Ruiter, Love (Matthews, 82), Browning (O'Shea, 80), Kone (Djilobodji, 82), Jones, Lens (Honeyman, 66), Cattermole (C), Ndong, Khazri (Gibson, 80), Vaughan, Maja (Asoro, 55).
Subs Not Used: Mika, Stryjek, Embleton.
Booked: Jones (60)
Goals: Maja (5), Lens (8), Jones (42)
Bradford (4-4-1-1): Sattelmaier, McMahon, Vincelot, Knight-Percival, Chicksen, Gilliead, Devine (Trialist), Reeves, Law (Taylor,74), McCartan (Taylor, 74), Poleon (Patrick, 74).
Subs Not Used: Doyle, Kilgallon, Barr.
Goals: McMahon (pen, 65), Trialist (90)
Referee: Geoff Eltringham
Attendance: 3,902 (999 Sunderland)