The captain of the Baggies bravely dove in front of the teenager's second-half shot to maintain a hard-fought 0-0 draw in a game that was mostly controlled by the Wearsiders. The intense match at the Stadium of Light was witnessed by a crowd of 36,733 spectators.
Regis Le Bris' men, who travel to leaders Sheffield United on Friday night, went into the game having drawn their last four against a side which had taken a point in seven of the last eight outings, and it was perhaps inevitable that there would be no winner as the hosts extended their unbeaten run to 10 games and the visitors theirs to nine.
Alex Palmer was called upon to make his first save with eight minutes gone when, after miskicking at the first attempt, striker Wilson Isidor sent in a deflected follow-up which the Albion goalkeeper needed two attempts to grasp.
Patrick Roberts blasted an 11th-minute free-kick wastefully into the defensive wall after Black Cats old boy Josh Maja had been penalised for handball, although the West Brom striker might have made amends in short order, but mistimed his attempt at a volley from Fellows' cross.
TrendingThe visitors failed to make the most of Karlan Grant's 23rd-minute surge upfield after muscling teenager Tommy Watson off the ball, but it was the hosts who started to turn the screw once more.
However, an increasingly scrappy game yielded few openings of note, although Kyle Bartley, drafted into the Baggies' starting line-up after the warm-up, had to block Watson's driven 37th-minute cross after he and Roberts had worked a clever short corner.
After a tepid conclusion to the first half, Sunderland returned determined to pick up the pace with Roberts and Rigg attempting to inject the devilment which had been largely lacking before the break.
It was Rigg's 58th-minute pass to overlapping full-back Luke O'Nien which allowed Isidor to stab home his cross from close range, but an offside flag quickly killed the cheers of the home fans.
Rigg and Jobe Bellingham both skied long-range attempts over as the home side's desperation mounted, but it took Mowatt's 69th-minute block to thwart Rigg after substitute Eliezer Mayenda had pulled the ball back.
Roberts steered Hume's cross just past the far post, before Dan Ballard's goal-line clearance prevented substitute Lewis Dobbin from snatching victory against the run of play six minutes from time.
Sunderland's Regis Le Bris:
To follow...
West Brom's Carlos Corberan:
To follow...