The pressure is building up! Middlesbrough fans everywhere are biting their fingernails to the hilt in the hope that the squad is not considerably weakened come the start of February.

Transfer stories concerning Emmanuel Latte Lath and Ben Doak continue to circulate, while there is also the potential threat of losing further players. If Boro can hang on to the key members of the squad then they will be in a strong position to carry on the push for a top six place. If not, then it’s crucial that replacements are brought in. We know that Boro have a list of potential targets should they need to use it.

The bottom line is that if the squad is quite obviously weaker come February, then there will be a negative feeling created both in and out of the dressing room. The problem is that January is not an easy time to bring in effective players, as Boro have found to their cost in the past.

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In fact it can be a minefield. Boro made many more disappointing January signings than influential ones over the past 20 years. So what is the calibre of player that Michael Carrick is looking for if he needs to move into the market? Which players can come in and make an immediate impact? I’ve trolled the record books and come up with some of the players who were signed in January and produced the goods. These are the kind of players who might make all the difference.

1 Gaston Ramirez

A massive, massive signing. The Uruguayan midfielder was the major inspiration behind Aitor Karanka’s side storming to automatic promotion in 2016. Ramirez had been treading water at Southampton and during a loan spell with Hull City, but Karanka’s faith in him paid major dividends.

Not only did Gaston lead Boro into the Premier League, but he revived his own career at the same time. He scored seven goals in 18 games and created many more. It appeared to be a great bit of negotiating when Boro got Ramirez’s name on a permanent contract during the summer.

Ironically, as Boro struggled in the top flight, Ramirez appeared to lose his appetite. He could have done better, and helped the team at the same time, but failed to make the same impact and it was obvious, especially after Karanka’s sacking, that Ramirez would be on his way. He went on to make a huge impact in Italy with Sampdoria and Boro made a healthy financial profit on his transfer fee. Even though he eventually lost his way on Teesside, the single season we have enjoyed in the top flight in the past 15 years might not have happened without him.

2 Daniel Ayala

The Spanish centre-back was a boy wonder who had joined Liverpool as a teenager, but was eventually moved on to Norwich City. He failed to impress at Carrow Road. Yet he was another inspired signing by Karanka when he signed a permanent contract in January, 2014, following a previous emergency loan deal.

Karanka needed a strong centre-back as the foundation of his defence-based system and Ayala proved to be that man. He quickly established himself in the Boro line-up and inspired his team-mates with his no-nonsense approach at both ends of the pitch. Ayala was a constant threat at corners. He scored 26 goals in his 229 appearances for the club, before moving on to Blackburn.

3 Chris Riggott

The centre-back was signed by Steve McClaren from Derby County as part of a double deal along with striker Malcolm Christie. Unfortunately Christie’s Boro career was badly affected by injuries, while Riggott initially faced heavy first team competition from the likes of England duo Gareth Southgate and Ugo Ehiogu.

Yet Riggott dug in and broke through on merit, establishing himself as Southgate’s regular partner and going on to play in the UEFA Cup Final – after scoring a crucial goal in the semi-final second leg against Steaua Bucharest. Injuries later badly affected his career at the club, but he had proved himself a top, top signing.

4 Doriva

The Brazilian midfielder was signed at the same time at Riggott and Christie, though Boro initially overlooked him and his arrival was announced somewhat later. He was secured on loan from Celta Vigo, where he had spent an uneventful season following a notable spell with Sampdoria. It might have been assumed that Doriva was going to be essentially a squad player, but he very quickly established himself as a key member of McClaren side with solid defensive midfield displays. As a result he was a leading light as Boro carried off their first major domestic trophy when winning the Carling Cup Final at Cardiff in 2004.

5 Finn Azaz

It’s early days yet for Azaz who continues to gain in stature with an increasingly important presence in the Boro’s No 10 role. The Republic of Ireland international was an astute signing from Aston Villa last January, after making a huge impact in a loan spell at Plymouth Argyle.

He blew hot and cold last season but his confidence has dramatically risen this term and he is now arguably the crucial cog in Carrick’s attacking machine, both in creating goals and scoring them. There are still the odd games where Azaz is edged out by opposition man-marking. But if Boro are going to be a top six side this season, then Finn will play a key role in making it happen.

6 Scott McDonald

The Aussie striker was signed from Celtic by Gordon Strachan in 2010 when the manager utilised by the gained from the transfer of Adam Johnson to Manchester City. He was a virtual member of the Boro line-up for three and a half seasons, under Strachan and Tony Mowbray, and finished up top scorer on two occasions, both times reaching double figures. McDonald’s total of 37 league goals for the club puts him in second place behind Britt Assombalonga in the club’s list of all-time Championship goalscorers.

7 Cameron Archer

The young striker was brought in on loan from Aston Villa by Carrick with a view to add extra spark to an attack which was primarily dominated by Chuba Akpom. Archer did exactly that, forming a superb attacking partnership with Akpom and scoring vital goals which ensured that Boro ended the campaign in the play-offs.

He scored 11 goals in 20 appearances which suggests that he might have passed the 20-goal mark had he been here all season. In fact if Boro had been capable of signing Archer permanently, it’s fair to assume he would still be rattling them in for the team.

8 Mo Besic

One of Tony Pulis’s first signings, the Bosnian midfielder was brought in on a six-months loan from Everton which was later extended by another year. Besic was a near regular throughout his time on Teesside, helping Boro to reach the play-offs in his first season. His strength was his defensive skills but he also liked to push forward whenever possible and created plenty of assists.

9 John Obi Mikel

The Nigerian international was a hugely talented player who had operated at the highest level for many years with Chelsea. He had been playing in China for a couple years before Pulis brought him in, on a short-term contract, to try to bolster a side which was struggling to gain a play-off place. Mikel added terrific strength in midfield, but his legs were not as strong as they were in past years, and it was a pity that Boro had not been able to sign him earlier.

10 Jordan Rhodes

Jordan was one of the game’s most prolific goalscorers from spells with Huddersfield and Blackburn when Karanka signed him for a fee of around £10m in January, 2016. Boro were struggling to keep their heads above water in the Premier League at the time, so Rhodes was seen as the man who might come up with enough goals to save their skins.

In the event Rhodes did not always get the hoped-for pitch time. In many respects I felt sorry for him because Karanka’s one-striker system did not seem to suit him. He still scored six goals in 18 appearances in a struggling side and might have been more productive with an increased attacking plan.