Chelsea grabbed a last-gasp winner in stoppage time to beat Leeds United 3-2 and bag all three points in the Premier League on Saturday.Raphinha scored the opening goal of the game. The 24-year-old scored from the spot after Marcos Alonso gave away a penalty as he took down Daniel James in the box. The Spaniard soon redeemed himself as he set-up Mason Mount with a flawless cut-back for Chelsea's equalizer.Chelsea doubled their advantage after the restart as Jorgingo slotted one in from the spot. The visitors upped the ante and tried to level the scores, but Chelsea hung on. Eventually Leeds' persistence paid off as Joe Gelhardt scored one in the 83rd minute of the game to pull the scores level. The game looked all set for a draw when Antonio Rudiger won another penalty for Chelsea in stoppage time. Jorginho calmly tucked it away to seal the win for the hosts.Chelsea FC@ChelseaFCYou love to see it! 😍#CheLee10:25 AM · Dec 11, 2021308406191You love to see it! 😍#CheLee https://t.co/LQ1ctWhMvlOn that note, here's a look at the five talking points from the game:#5. Chelsea's defense needs a fixAntonio Rudiger in action against Leeds UnitedThomas Tuchel will be concerned about the goals his side have conceded this week. Chelsea have let past eight goals in their last three games in all competitions. Before December, Chelsea had never conceded two goals in a single game throughout the season.Although the back-line was rock solid for the majority of the game, there were moments where they had lapses in concentration. The back-line switched off on key occasions that granted the visitors enough room to exploit. Tuchel will have many things to think about after today's performance.#4. Mason Mount is having an exceptional seasonMason Mount celebrates after scoring a goalMason Mount scored the first equalizer for Chelsea. The Englishman tucked one away in the 42nd minute of the game after receiving a perfect cut-back from Alonso.With this goal, Mount became Chelsea's leading goal scorer in the Premier League this season with six goals. The 22-year-old has directly contributed to 10 goals this season. He has been in exemplary form recently and has scored three and assisted twice in his last three appearances in the league.Chelsea FC@ChelseaFCFirst time. Bang. 💥#CheLee9:24 AM · Dec 11, 2021119891094First time. Bang. 💥#CheLee https://t.co/Dni9BadPzb