The 22-year old Australian midfielder netted his side’s second goal to make it 3-2 to the visiting Foxes who were served by a Yakubu Aiyegbeni hat-trick.
The Nigerian striker, on loan at Leicester from Everton, scored in the 5th, 45th and 49th minutes against his former club with Marvin Emnes giving ‘Boro some hope with his 14th minute finish.
With the score at 3-1 in favour of Leicester, the returning Williams, who has played just five times this season because of groin injuries, produced a special goal in the 55th minute when he flicked it up to himself before volleying home from 25 yards.
Drama ensued after that goal when Leicester’s Jeffrey Bruma handballed in the area, giving the home side a penalty, but Julio Arca missed from the spot before Bruma was sent off for a second yellow.
With a man advantage, the Tessiders took control and managed to grab a point thanks to Stephen McManus’ last-minute header which allowed Tony Mowbray’s men to remain 18th on the table.