Luke Moore, who has missed the last two matches with a knee problem, resumed training earlier this week and was on Thursday joined by midfielder Graham Dorrans (bruised foot).
Scott Carson is also expected to make his comeback on Friday after an ankle injury and all three players are expected to be in contention to face the Royals, as well as winger Jerome Thomas, who returns from suspension.
Internationals Marek Cech, Robert Koren and Gonzalo Jara have not reported any injuries following their exploits for their respective nations and they will also return to the fold on Friday.
However, Di Matteo will assess Jara closely before deciding whether he will feature at The Hawthorns, with the defender having only recently flown back from South America.
Yet the Baggies will be without midfielder Chris Brunt after he sustained a calf strain last time out in the goalless draw at Preston, while long-term absentees Ishmael Miller, Neil Clement (both knee) and James Morrison (heel) also remain on the sidelines.
Reading manager Brendan Rodgers has a full-strength squad to pick from.
Polish striker Grzegorz Rasiak is in contention to start, having shaken off a knock which prevented him from featuring in the Royals' 2-0 home defeat to Middlesbrough before the international break.
Shane Long had been struggling with an ankle problem but he is edging closer to full fitness after being involved in the Republic of Ireland squad this week.
Noel Hunt has fully recovered from a foot injury which has plagued him since the end of last season. The 26-year-old is set to feature for Rodgers' men, who are fourth from bottom after recording just two wins from their opening 11 league fixtures.