Merchant comes back into the fold for the first time since last month’s victory of Italy, looking to improve her impressive record in the Red Rose which has seen her score 37 tries in 43 appearances.

The versatile Emily Scarratt will wear the No.15 shirt, meaning Natasha Hunt moves from full-back to scrum-half for the visit of Ireland, while Kim Oliver starts at centre.

England have scored 138 points in their four games so far this year, conceding just six in reply, but could still lose their Six Nations crown if Ireland leave Esher with the win and score 24 points or more.

And with that in mind Street is taking nothing for granted with a potential Grand Slam up for grabs, hoping his changes bring about some extra firepower to down Saturday’s opponents.

“Kat gives us some great experience in the backline and she is a potent attacking player and that could be vital on Saturday in what I am expecting to be a very close game,” he said.

“I have made a few tactical tweaks in the backline which will give us some new attacking options whilst I believe it will also strengthen our game for this vital match.

“Our pack really set the marker against France last weekend, producing outstanding ball with huge physicality and we need them to replicate that against Ireland.

“This has been Ireland’s best ever Six Nations season. They came close to beating France away and have scored a lot of points.

“This is the first time they have been in the running to win the Six Nations championship and they have a real fighting chance.

“They will be really up for it and we will be taking nothing for granted. They have got great pace out-wide, a good set-piece and Niamh Briggs’ kicking game is impressive.”

England

15. Emily Scarratt (Lichfield)

14. Katherine Merchant (Worcester)

13. Rachael Burford (Richmond)

12. Kimberley Oliver (Bristol)

11. Kay Wilson (Bristol)

10. Katy Mclean (Darlington Mowden Park Sharks)

9. Natasha Hunt (Lichfield)

1. Laura Keates (Worcester)

2. Victoria Fleetwood (Lichfield)

3. Sophie Hemming (Bristol)

4. Rowena Burnfield (Richmond)

5. Tamara Taylor (Darlington Mowden Park Sharks)

6. Marlie Packer (Bristol)

7. Margaret Alphonsi (Saracens)

8. Sarah Hunter (Lichfield)

Replacements:

16. Amy Turner (Richmond)

17. Rochelle Clark (Worcester)

18. Rebecca Essex (Richmond)

19. Hannah Gallagher (Saracens)

20. La Toya Mason (Wasps)

21. Ceri Large (Worcester)

22. Michaela Staniford (Wasps)