Williams has not played a single minute of football for Boro's senior side this season after sustaining a serious pelvic injury last spring.
The Australia international was playing as a central midfielder under former Boro boss Gordon Strachan, but could revert to a defensive position at either rightback or centre-half to help assuage Tony Mowbray's current selection problems.
He will hope to be included in the squad for Saturday's Championship away game at Reading having stepped up his rehabilitation yesterday afternoon.
Williams was part of a youthful Boro reserves side that suffered their first league defeat of the season at the hands of their local rivals.
Hartlepool took the lead in firsthalf stoppage time, with Paul Johnson flicking on Darren Holden's cross, and Michael Mackay converting from close range.
Boro equalised in the early stages of the second half, with Mickael Tavares creating space on the edge of the area before drilling a low strike past Hartlepool goalkeeper Andy Rafferty.
However, Paul Johnson headed Pools back into the lead with 16 minutes left, and Rafferty saved well from Tarmo Kink as Boro pushed for another equaliser.
MIDDLESBROUGH: Ripley, Oliver (Pilatos 46), R Williams (Rivers 84), Haas, Reach (Sirrell 46), Smallwood, Atkinson, Tavares, Kink, Halliday, Park.
HARTLEPOOL: Rafferty, Lucmendy (Purvis 63), Holden, Richards, P Johnson, Bjornsson, Mackay, Yantorno (Rowbotham 71), Boyd (Martin 63), Behan, Birkbeck.
Source: Northern Echo
Source: Northern Echo