AFC Telford United manager Liam Watson classed his side's 1-1 draw at Altrincham as a "missed opportunity" as they failed to get back within a point of the Conference North top two.
The Bucks failed to push home their early advantage after midfielder Mike Grogan's sixth-minute opener.
Andy Owens missed two chances before the Robins levelled on 33 minutes.
Against the run of play, a mistake at the back by Dan Preston let in James Walshaw to equalise.
Altrincham took control in the second half, Walshaw firing wide before Gianluca Havern hit a post.
But Telford hung on in the end for the point which sees them slip to fourth in the table, Boston having now moved above them on goal difference after winning at Histon.
Tuesday night's hosts Altrincham, their promotion rivals, stay one place shy of the play-off spots.
With Conference North leaders North Ferriby United having been absent on FA Trophy quarter-final duty on Saturday, Telford's 4-2 win at home to Guiseley had closed the gap back to within four points. But Telford now have to look to Saturday's trip to Oxford City to make further inroads.
"I couldn't fault the players' efforts," Telford boss Liam Watson told BBC Radio Shropshire. "But it's definitely a missed opportunity."