Everton defender Ramiro Funes Mori has warned captain Phil Jagielka he has no intention of giving up his place in the team without a fight.
The Argentina defender has more than ably filled the considerable void left by a knee injury which has sidelined the Toffees skipper since the end of October.
Jagielka has been an unused substitute in the last two matches but Funes Mori, who scored his first goal at Goodison Park in the 2-1 Capital One Cup semi-final first leg victory against Manchester City, intends to make it as difficult as possible for the returning 33-year-old.
"He was injured and in my moment I had to come in and play and take advantage of my time on the pitch," he said.
"He is the captain but I have done my job so he has to come back again and play for a spot. We will both have to fight for a place."
Funes Mori has surprised many with how well he has settled in following his arrival late in the transfer window from River Plate.
Some questioned his £9.5million transfer, which made him the club's most expensive defender, after the price almost doubled in the final days of the window after it emerged the player was entitled to 50 per cent of any fee under the terms of his River Plate contract and Everton obliged rather than allowing the deal to fall through.
In hindsight it appears to have proved a more than worthwhile down-payment as the 24-year-old has provided essential cover for Jagielka and has undoubtedly prospered from playing alongside Stones for an extended period.
"He is a top player and has a lot of quality and I think I am playing with a great central defender," he added.
"We have become more confident as we have got to know each other and that has produced positive results.
"I speak a lot with John during the game and we talk to each other a lot so we can cover each other's backs."
The centre-back's goal, his second of the season, on the stroke of half-time was followed by Jesus Navas' equaliser and Romelu Lukaku's 19th strike of the season in the second half as Everton secured a narrow advantage to take to the Etihad Stadium in three weeks.
It raised the prospect of an all-Merseyside Wembley final after Liverpool's 1-0 win at Stoke the previous night but Funes Mori knows the tie is far from over.
"We are taking it game by game," he said.
"We had a perfect performance against Manchester City and we have to think about the second leg and not to get ahead of ourselves about what is coming
"City have a very strong squad, they have top players, but we also can play and have strength. We will have to be good defensively.
"The whole team has built a lot of confidence in defending and being strong at the moment.
"It is very important for everyone to make sacrifices for each other because we know we have a skilful team with a lot of qualities so we know we can score goals."
Everton made their first signing of the transfer window when Grasshoppers' forward Shani Tarashaj agreed a five-year contract, although he will not be available until the summer as he will be loaned back to his former club as a condition of the deal so he can complete his national service.
The Switzerland Under-21 is looking forward to developing under Roberto Martinez.
"I heard that he was a good manager and works well with young players individually - this is what I want to make me a better player," he said.
Martinez added: "Shani is an enormous young talent in Swiss football who, without a doubt, will have a great future.
"We're delighted to have found a young player who believes that our club is the perfect step for him to enhance his quality and to grow his career."