Midfielder N'Golo Kante looks set to miss Leicester’s next two matches because of a hamstring injury.
The Frenchman was substituted after 70 minutes of Leicester's 1-0 win at home to Norwich City with the problem.
Leicester play West Brom at home on Tuesday and then travel to Watford on Saturday as they look to consolidate their lead at the top of the table.
Kante, who has been in superb form in his first season with the Foxes, was replaced by fellow midfielder Andy King, with whom Ranieri was impressed.
And the Italian is positive King can quickly gel with Daniel Drinkwater in the absence of the 24-year-old.
Ranieri said: "Kante I think will lose the next two matches. I hope only two. It is a little painful in his hamstring. He has been suffering all the season and now it's a little more charged, so we want to give him some rest.
"All the season he had a problem in the other leg, and now in the new leg. Maybe he made some compensation. It's extraordinary but I am very confident because we have King to play with Drinkwater, and I am very confident in him. No other injuries.
"Now I am thinking between Daniel Amartay and Danny Simpson, and tonight I decide. The day before is OK."
Leonardo Ulloa scored Leicester's 89th-minute winner at the King Power Stadium, which has maintained their two-point advantage over Tottenham in the battle for the Premier League title.
Ranieri said: "When you play against teams like Norwich, and West Bromwich, we had to be patient and find the solution. The first match against WBA was tough. They scored first, and we slowly got better. I am waiting the same this time."
Meanwhile, Foxes right-back Danny Simpson is available to play against Albion after missing that win over the Canaries following his red card against Arsenal.
However, Daniel Amartey could continue in defence after impressing during his first-team debut at the weekend.