When Manchester City and Chelsea lock horns at the Etihad Stadium later today, the UEFA Champions League final will undoubtedly be the major talking point of the game. The all-English final is set to take place later this month after both sides recorded convincing victories against Paris Saint-Germain and Real Madrid respectively in the semi-finals, as they prepare to go head-to-head for club football's biggest honor.FtumIn what has been dubbed the dress rehearsal ahead of the big European showdown, Pep Guardiola and Thomas Tuchel will look to analyze each other's strengths and weaknesses.Chelsea have been in stunning form since Tuchel took over the reins from Frank Lampard and have catapulted to fourth in the Premier League table. The Blues have booked their place in the FA Cup final after beating Manchester City in the semi-finals and also have a UEFA Champions League final to look forward to against the same opponents.Pep Guardiola's side, on the other hand, could be crowned Premier League champions this week and will look to seal their third domestic crown in four years with a victory at home.Chelsea's resurgence under Tuchel has been one of the most intriguing subplots of an eventful Premier League season and the German tactician will look to scalp another feather in his cap by getting another win against Guardiola.However, Chelsea will have their work cut out for them if they are to beat the Cityzens on their home turf. On that note, here are five reasons why the Blues could struggle to beat Manchester City later today.#5 Thomas Tuchel's horror record vs Pep GuardiolaManchester City v Chelsea: Emirates FA Cup Semi FinalThomas Tuchel and Pep Guardiola have locked horns six times over the years and the German has emerged victorious on just one occasion. Having previously managed Mainz, Borussia Dortmund and Paris Saint-Germain, Tuchel has been on the wrong end of a handful of hammerings against Guardiola and will look to avoid another one later today.First it was Guardiola v Mourinho.Then Guardiola v Klopp.Now Guardiola v Tuchel is just getting started 👀✍ @jonnysmiffy— Goal News (@GoalNews) May 8, 2021His only victory against the legendary Spaniard came earlier this season when Chelsea and Manchester City squared off in the FA Cup semi-finals. The Blues caused a major upset and destroyed City's quadruple hopes, as they recorded a 1-0 victory courtesy of a goal from Hakim Ziyech.Tuchel has won just once against Guardiola and will hope for a similar outcome to what happened in the FA Cup final when the two sides face off at the Etihad Stadium.#4 Manchester City victory's against Chelsea could seal Premier League titleManchester City v Huddersfield Town - Premier LeagueManchester City's coronation is only a matter of time away, but the Cityzens will look to wrap things up quickly to prepare for the UEFA Champions League final. With a victory against Chelsea, Guardiola and co could mathematically seal the title with three games to spare irrespective of Manchester United's results in the coming weeks.Is today the day 🏆— Sky Sports Premier League (@SkySportsPL) May 8, 2021Chelsea were involved in the game that sealed the title for Liverpool last season, as their 2-1 victory in the reverse fixture handed the Reds their first league title in over 30 years.Manchester City are expected to field a full-strength XI, so Chelsea will have to be on their toes to prevent what could be a title-sealing victory for the home side.