The DHL Stormers start their title defence against the Irish side, in a match that kicks off at 14h30 on Saturday at the Danie Craven Stadium and will be broadcast live on SuperSport.
The 19-year-old Hartzenberg will line up alongside Dan du Plessis in midfield, while out wide speedster Angelo Davids returns from a stint with the Springbok Sevens team to join Blommetjies and Seabelo Senatla in the back three.
Manie Libbok and Paul de Wet form the starting halback combination, with Godlen Masimla and Junior Springbok captain Sacha Mngomezulu among the replacements.
Ernst van Rhyn captains the team from the second row, alongside Marvin Orie and behind a pair of experienced props in Ali Vermaak and Brok Harris, with Andre-Hugo Venter at hooker.
Evan Roos is at the back of the scrum, with Junior Pokomela and Hacjivah Dayimani on the flanks, while there are six forwards in Kwenzo Blose, Chad Solomon, Neethling Fouche, Adre Smith, Marcel Theunissen and Willie Engelbrecht ready to make an impact as replacements.
DHL Stormers head coach John Dobson said that everyone is looking forward to seeing what the new players bring on what should be a memorable occasion in Stellenbosch.
“We have seen the likes of Clayton, Suleiman and some of the others show some real promise in our pre-season and it will be good to see how they react on Saturday," said Dobson.
“We have got an exciting blend of youth and experience, along with more than a few players who really stapped up for us consistently last season.
“The players can’t wait to get going again and we know how important it will be to make a strong start this week, especially as we are playing in a rugby-mad place like Stellenbosch on what should be a great day for it.”
DHL Stormers: 15 Clayton Blommetjies, 14 Angelo Davids, 13 Suleiman Hartzenberg, 12 Dan du Plessis, 11 Seabelo Senatla, 10 Manie Libbok, 9 Paul de Wet, 8 Evan Roos, 7 Hacjivah Dayimani, 6 Junior Pokomela, 5 Marvin Orie, 4 Ernst van Rhyn (captain), 3 Brok Harris, 2 Andre-Hugo Venter, 1 Ali Vermaak. Replacements: 16 Chad Solomon, 17 Kwenzo Blose, 18 Neethling Fouche, 19 Adré Smith, 20 Marcel Theunissen, 21 Willie Engelbrecht, 22 Godlen Masimla, 23 Sacha Mngomezulu.