|Specsavers County Championship Division Two, New Road, day two|
|Northamptonshire 551: Keogh 154, Crook 145, Barrett 114*|
|Worcestershire 153-1: Mitchell 86*, Fell 61*|
|Worcestershire (2 pts) trail Northamptonshire (4 pts) by 398 runs|
Northamptonshire tailender Chad Barrett made an unbeaten century on his debut, to back up Steven Crook's career-best 145 as Worcestershire were made to toil for a second day running at New Road.
Barrett finished on 114, the highest score by a Northants number 10, to back up the contributions of Crook and Rob Keogh (154) as the visitors made 551.
But Worcestershire then responded well in the day's final session.
Daryl Mitchell (86*) and Tom Fell (61*) were both there at the close on 153-1.
So far, the pair have shared an unbroken stand of 145 - matching Northants' ninth-wicket partnership earlier between Crook and Barrett.
Inside 34 overs, they fell just nine runs short of the county's ninth-wicket record, but they still surpassed the previous best for the ninth wicket in matches against Worcestershire, the 137 shared by Jack Timms and Reg Partridge at Stourbridge in 1934.
Crook's career-best 145 overtook his 142 not out last summer against the Australian tourists, while South African Barrett's innings beat the 106 by Gus Williamson, batting at 10 against Cambridge University in 1960.
On a day when Worcestershire vice-captain Joe Leach (3-121) passed the landmark of 50 Championship wickets for the second successive season, the home side lost England Lions all-rounder Brett D'Oliveira for an 11th-ball duck.
But captain Mitchell then weighed in with his best score of the summer, well supported by Fell, before bad light ended play prematurely.
Worcestershire director of cricket Steve Rhodes told BBC Hereford & Worcester:
"Anyone coming in at number 10 and getting a hundred has done a great job. Jack Shantry has done that sort of thing for us.
"It is a flat wicket and our two guys played really well, Tom Fell and Daryl Mitchell, who is nicely poised for what could be his first century of the season.
"They have just started to get the ball to reverse a little bit and that will be a little bit trickier. We need to get a big score and potentially pull out if we avoid the follow-on.
"But that's easier said than done. We've got to get there. We've got nearly another 300 runs to go and that is ultimately our plan at the moment."
Northants century-maker Chad Barrett told BBC Radio Northampton:
"I couldn't have wished for a better Championship debut. I've had to wait two years for my opportunity. It was a decent wicket and I had to make the most of it.
"Two years waiting to play a second first-class game (the first was against Sri Lanka) is a long time. You think to yourself 'Am I going to play another one?'
"When I got the nod, I thought when I have a bat or a bowl, I've just got to show what I can do.
"We said we'd try to get to 500 which is a big milestone and to get to three figures myself was my own milestone. I had faith in Ben Sanderson while I got there. I know he can hold a bat and is more than capable."