It has been reported Ritchie, who withdrew from the Scotland squad through injury over the weekend, was back with the rest of the squad today after being assessed by the club's medical staff.
The midfielder played 87 minutes of Scotland's 1-0 friendly defeat by Costa Rica on Friday evening, but headed back to the north east before Tuesday night's 1-0 win in Hungary.
He worked alone with the Magpies' fitness coach on Tuesday, but was given the green light to join the rest of the group on Wednesday morning.
The 28-year-old, who has scored in two of his last three games for the Magpies, including a winner against Manchester United, is a key member of Benitez's team and his availability this weekend will delight the Spaniard.
His team currently sit in 13th place in the table on 32 points, but just four points clear of the drop zone with eight games remaining.
Victory over Town on Saturday, who are two places and a single point worse off, would edge them closer to Benitez's 40-point target for the season and significantly boost their chances of remaining in the top flight.