With Virat Kohli rested, India could hand a debut to young Shubman Gill.
Kohli is rested for the final 2 ODIs and the 3-match T20I series against New Zealand.
Doug Bracewell and Ish Sodhi have been released for the fourth and fifth ODIs.
At 34, Somerville could become the oldest Test debutants, behind the late Herb McGirr, who debuted in 1930 at the age of 38.
Corey Anderson was not selected on account of an injured heel sustained during the last match and will fly back to New Zealand.
The second and final Test begins in Christchurch on Friday.
New Zealand and West Indies will lock horns for the penultimate ODI at Christchurch on Saturday (December 23).
Ross Taylor has not played T20Is for New Zealand since March 2016.
Ish Sodhi in all likelihood will replace Astle in the ODI squad.
Pakistan head coach Mickey Arthur has considered the inclusion of spinner Todd Astle as an `interesting choice` by New Zealand for the upcoming two-Test series.
After successful win over Sri Lanka, New Zealand will play hosts to Pakistan for three One-Day Internationals (ODIs) and three Twenty20 Internationals (T20Is)
Todd Astle is a leg-spinner with a handy batting ability.
Todd Astle had been named in the New Zealand Twenty20 squad against Pakistan as to have a look at him keeping in mind the ICC
Luke Ronchi's whirlwind century helped New Zealand A amass 310 all out as India A trailed by 304 runs at the end of the second
Skipper Ross Taylor (53 not out) and debutant Todd Astle (32 not out) put on an unbeaten partnership of 79 runs in the second innings
01 Jul, 2022 15:00 IST
Edgbaston, Birmingham
Sri Lanka vs Australia - 2nd Test
08 Jul, 2022 10:00 IST | 04:30 GMT
Galle International Stadium, Galle
10 Jul, 2022 15:00 IST | 09:30 GMT
Titwood, Glasgow
11 Jul, 2022 15:00 IST | 09:30 GMT
Cambusdoon New Ground, Ayrshire
13 Jul, 2022 15:00 IST | 09:30 GMT
Titwood, Glasgow
14 Jul, 2022 15:00 IST | 09:30 GMT
Titwood, Glasgow
India beat Ireland by 4 runs
England vs New Zealand - 3rd Test
England beat New Zealand by 7 wickets
India beat Ireland by 7 wickets
Zimbabwe vs Afghanistan - 5th T20I
Match over
Zimbabwe vs Afghanistan - 4th T20I
Match over