People seem to underestimate how vital Hazard was to chelsea. Chelsea heavily depended on him for goals and assists in Sarri's season, he contributed to over 50% of Chelsea's goals the season he left, he essentially carried the team to the Europa leage and 3rd.
No one saw where Chelsea's goals were coming from, Willian and Perdro lack productivity and end-product. Giroud hadn't scored more than 10 in a season, Pulisic had question marks about him, he had lost form and his place at Dortmund to an 18 year old before joining Chelsea.
Only signing Lampard made was making the Kovacic loan permanent, and Kovavic was so sup par under Sarri that most of the fan base didn't want him permanently.
Also the fact that Lampard was only in his 2nd year of management with a transfer ban was the reason a lot of people had chelsea finishing out of the top 4.
1. For all the crap that Sarri got from the press, fan base and punditry. Chelsea still finished 4th and won the Europa league. Lampard was not inheriting a poor squad. He infact inherited a squad that had been playing with the hand brake on. Yet it was still to be strengthened by a talented loan at of players. Plus permanent additions of Kovacic and Pulisic.
2. It is true Hazard carried Chelsea the previous season. Yet still it had a lot to do with how Sarri set up. Under Conte for example most those same players had more end product. It was not too much of a stretch to expect the goal out put overall to improve under Lampard.
3. There is a myth that has been going around that Pulisic lost his place at Dortmund due to a dip in form. In truth it was more down to his desire to move on. He refused to renew with Dortmund. They put all sorts of pressure on him but he refused to cave. So they then simply pushed Sancho over him.
4. Kovacic may have not been superb in his first year. But only a brave person would have dared think he wasn't an excellent acquisition.
5. The only thing that could have reasonably worried people was Lampard's in experience as a boss. But the fact that Chelsea had a transfer ban and were determined to finally give their youth and loan army a chance. After seeing how the likes of Tomori and Mount faired under him and Morris at Derby, In my opinion, there was a lot to be excited about Chelsea.
Lampard definitely deserves credit for a job well done. But I don't agree he had it worse than his counterpart Solksjaer. I personally expected him to finish ahead of Spurs this season. I'm actually not surprised at all that it happened. He simply justified the faith the Chelsea owner rightly had in him in my book.