Yorkshire took complete control of their County Championship Division One clash against Northamptonshire on a record-breaking third day at Wantage Road.
Adam Lyth and Alex Lees put on 375 for the opening wicket with the former registering a brilliant 230 in 546-3 declared before the visitors reduced the hosts to 66-3 at the close.
That left Northamptonshire 365 runs behind with seven wickets left as they looked to avoid slipping to a fifth defeat of the season.
Yorkshire resumed on 237-0 and made steady progress adding to it as they saw off the second new ball with Lyth bringing up his 150 off off 279 balls.
The 300 partnership came up when Lyth hit Matthew Spriegel over long-on to take himself and Lees past Percy Holmes and Roy Kilner’s Yorkshire record for any wicket against Northamptonshire.
Lyth brought up his double hundred off 351 balls with a four off Azharullah but Northants eventually had their breakthrough as Lees fell for 138.
Maurice Chambers took the catch off Spriegel at mid-on to end the mammoth opening partnership - the fourth highest for any wicket in Yorkshire history and biggest of the County season thus far.
Australian Aaron Finch was bumped up the order to No 3 on his four-day debut for the club and hit a brisk 63 off 64 balls. Lyth was eventually out for 234 with Jack Leaning (52 not out) also having an impact with his maiden first-class half-century.
Stephen Peters and James Middlebrook got the home chase off to steady start but the wheels came off when the latter was caught behind off Tim Bresnan to leave them 31-1.
Just one was added before Lyth caught Peters off Bresnan at second slip for 26 and, when Jack Brooks had Alex Sales lbw for a duck three balls later, the home side were in considerable trouble.