Boston United forced to settle for a point at Bradford Park Avenue as they fail to make dominance pay off
Will Longbottom had put the hosts ahead in the 66th minute only for the Pilgrims to respond within 60 seconds.
But that was the only breakthrough for Craig Elliott's side who couldn't pick up three points despite their dominance.
The result sees them miss out on the chance to move up to fourth in the National League North, United remaining sixth in the table - but extending their unbeaten record to eight games in the heavy wind and rain at the Horsfall Stadium.
Elliott made three changes to his side, Andi Thanoj, Jay Rollins and Thewlis back in with Connor Dimaio, Terry Hawkridge and Fraser Preston making way.
Pilgrims loanee Pierce Bird had to be alert at the back post to hack away Luca Havern's header in the early exchanges.
United, who had enjoyed more of the ball but created little in front of goal to that point, began to get a foothold in the game with Thanoj testing host keeper Dan Atkinson, who was then called upon to tip away Joe Leesley's free kick and make a telling touch to a dangerous corner.
Jordan Burrow then saw two headed efforts fly wide of the target before United midfield stopper Tom Platt was forced off through injury, replaced by Paul Green.
But that change didn't affect the script as the Pilgrims continued to apply pressure, Thanoj seeing a free kick go the wrong side of the post.
Atkinson reacted superbly to keep out a long free kick which was nudged goalwards off a Bradford head but Boston kept getting closer.
Green's strike was parried by by the keeper before Mark Ross hacked Burrow's follow-up off the line.
The second half began with Thewlis forcing a save from Atkinson.
Park Avenue were forced to reshuffle following an injury to Ryan Toulson, with Isaac Marriott taking his place.
Atkinson claimed Green's drive at the second attempt after the 20-yard effort squirmed through his fingers towards goal.
Bird was once again in the right place as he deflected Adam Nowakowski's effort off target.
But from the resultant corner Longbottom handed the hosts a 66th-minute lead, forcing home from close range.
But a minute later and Boston were level, Leesley's deep cross nodded home by Thewlis.
The United striker, playing in his preferred striker's role, forced another block from the Bradford keeper and he cut from the left.
Thanoj flashed another effort wide before Boston's Ross Fitzsimons -named as the December National League North Player of the Month earlier today - pulled off the save of the game, fingertipping away Longbottom's low fizzer in the 88th minute.
Fitzsimons was called upon to hold onto Lewis Knight's tame stoppage time effort as neither side could force the winner.
BPA: Atkinson, Ross, Toulson (Marriott 59), Booty, Havern, Windass, Longbottom, Nowakowski, Dockerty (Johnson 76), Knight, Clee; Subs (not used): Sanyang, Hussain, Fawcett.
UNITED: Fitzsimons, Tootle, Duxbury, Platt (Green 18), Shiels, Thanoj, Burrow, Thewlis, Rollins (Preston 76), Bird, Leesley; Subs (not used): Garner, Dimaio, Hawkridge.
REF: Michael Barlow.
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