The Bluebirds captain pounced to secure a much-needed Championship victory on Saturday that will prove as crucial as any other the South Wales outfit will have this season.
And manager Dave Jones, celebrating his 100th win in charge of City, will be relieved to finally see some positive headlines as the cash-strapped club prepare to go back to the High Court on Wednesday over their unpaid tax bill.
The result, which secures a league double over Boro, comes on the back of successive defeats which have hit the club's promotion charge.
On the balance of play, it was a fair result despite a much improved second-half display from a Boro side who were well below par before the break, while both sides had reason to be unhappy with match-turning decisions made by referee Darren Deadman.
With all of Cardiff's problems - both on and off the pitch - Jones will have welcomed his side's dream start with open arms.
The ball found its way to Darcy Blake via a short corner, he chipped into the box and Gabor Gyepes was on hand to poke goalwards from where Bothroyd converted at the back post.
The hosts continued their fine start and the travelling Boro fans had to wait 20 minutes for their side to apply any sort of pressure in the final third although it failed to produce an attempt of note.
Jeremie Aliadiere was presented with a good chance to level matters for Boro in the 29th minute after a defensive mix-up between Anthony Gerrard and Adam Matthews but the Frenchman could only fire well over the bar.
Bothroyd stabbed wide at the other end as Cardiff continued to enjoy the better of the first half.
And a disappointing Boro were handed a let off just minutes before the interval as referee Deadman booked Chris Burke for diving in the area, despite his assistant appearing to flag for a penalty and the majority of those inside the Cardiff City Stadium feeling the same way.
Cardiff again started on the front foot as the game got back under way and Gavin Rae stooped to head wide with just two minutes gone.
But Leroy Lita, barely noticeable in the first half, wasted a great opportunity for Middlesbrough in the 49th minute when he headed over from six yards.
It was the home side who were this time let off the hook just before the hour mark as David Wheater appeared to head home Barry Robson's free-kick but the goal was seemingly disallowed by referee Deadman for handball, much to the annoyance of everyone in a red shirt and manager Gordon Strachan.
By now the encounter was a much more even contest with both sides creating half chances at either end as the game approached the final 15 minutes.
Cardiff keeper David Marshall was called upon to produce fine saves to deny Chris Killen and Gary O'Neil as Boro pressed, but it was Blake who came closest to a second for the hosts when he struck the crossbar with virtually the last kick of the game.