Manchester United host Manchester City in the first leg of their Carabao Cup semi-final tie at Old Trafford on Tuesday.

Here, the PA news agency looks at some talking points ahead of the derby clash.

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— Manchester City (@ManCity) January 5, 2020

United will hope for repeat of December derby win

Given their indifferent form this season and City's proven strengths, United were expected to struggle when the sides met at the Etihad Stadium last month. But City's biggest weakness, their vulnerability to the counter-attack, played to United's greatest strength. Utilising the pace of Marcus Rashford, Anthony Martial and Daniel James, United tore through City with a number of lightning raids, particularly in the first half-hour. They could easily have scored more than the two goals they managed in the 2-1 success. City have since been exposed again by Wolves and United may look for more of the same.

Guardiola could change approach

City boss Pep Guardiola is a man who tends to stick to his principles, regardless of results. He insisted he was happy with his side's performance against United last time around despite the defeat as, after all, they created more chances and dominated possession. In two-legged ties, however, he does sometimes opt for a more pragmatic approach. With United cutting through City with alarming ease last time, he may well take note and vary tactics.

Another trophy in sight for City

There is no doubt City will take this seriously. The Premier League title may well have gone but City still have plenty to play for and, having reached this stage, winning the Carabao Cup will be a clear aim. City have dominated this competition in recent years, winning it in four of the past six seasons. Another success would be a third in succession and an 11th major trophy in the past nine years. City have not lost a tie in this cup since losing to United in the fourth round in October 2016. They did not take their foot off the gas for Burton in last year's semi-finals, thrashing them 9-0 in the first leg, and there is little chance Guardiola will field a weakened side.

Tough keeper call for Solskjaer

United's back-up goalkeeper Sergio Romero will have given manager Ole Gunnar Solskjaer some food for thought with his performance in the goalless draw with Wolves at the weekend. The form of first-choice David De Gea has been a concern for some time now. The normally brilliant Spaniard has made a number of uncharacteristic and costly mistakes this season and some observers have suggested dropping him might do him good. Romero has kept six clean sheets in his last eight. It would be a bold call but Romero is certainly applying pressure.

United fitness concerns

Solskjaer has a number of worries ahead of the game. Defender Harry Maguire is the latest concern having suffered a knock against Wolves. He will be given a fitness test while Jesse Lingard and Anthony Martial will hope to overcome illness to feature. United also have a shortage of quality in midfield with Paul Pogba and Scott McTominay injured. City have close to a fully-fit squad with Nicolas Otamendi returning. Only Aymeric Laporte and Leroy Sane remain out but both could return in the near future.