Despite being down to 13 men - and at one stage, 12 - for the remaining 20 minutes, the Blue, Black and White grasped the game by the scruff of the neck in the closing stages to secure both try and losing bonus points.
Wing Will Muir crossed for the opening score in the first half but, following Ben Spencer and Paddy Jackson’s penalty trade, Ben Loader and Matt Rogerson went over for Irish.
Returning England international Anthony Watson scored ahead of Tom Parton, Loader and Curtis Rona dotting down in a period of ill-discipline for Bath which saw Muir sin binned and Tom Dunn and Charlie Ewels red carded.
The lack of numbers didn’t affect Bath’s spirit and they battled hard to claw their way back to within three through Josh McNally and Walker.
London Irish showed why they had such a formidable home record coming into the fixture; dominating possession for the opening two minutes, trying to find fortune on the outside.
From the kick-off they retained the ball for a consecutive two-minute spell but failed to make ground as they met a confrontational Bath defence. Jack Walker and Sam Underhill were particularly busy.
On the attack, Stuart Hooper’s men looked menacing. Number 8 Zach Mercer punched a hole for one of four first-half line breaks for the visitors whose offloading skills were sublime.
Two special pops in particular led to Muir collecting his third try in a week. Jonathan Joseph’s creativity set Tom Ellis on the charge and the ball was recycled quickly for Max Clark to carry, with the setting able to release his arm free and send the ex-England Sevens man over the whitewash.
Scrum-half Spencer cancelled out a Jackson’s three points with a long-range strike as Bath were defensively sound around the fringes, forcing Irish into mistakes.
The home side drew level on 24 minutes shortly after Ewels had received his first yellow card for unfortunate contact to Loader’s head. The Irish flyer dusted himself off to dance underneath the sticks moments later.
Spencer edged Bath back in front with a pinpoint kick at goal, however a stunning piece of play from Parton resulted in the lead changing hands again.
The full-back weaved his way 50 metres up-field and back rower Rogerson proved the beneficiary of his hard work, powering home from close range.
Bath responded well and were unlucky not to cross again before the break. The ever-impressive Spencer made ground via a cheeky snipe and Joe Cokanasiga rampaged on to his pass only to be hauled down at the last by the ankles.