Kepa Arrizabalaga has become a "massive issue" for Chelsea, claims Chris Sutton, with the former Blues striker saying "more business" is required from Frank Lampard in the next transfer window.
Roman Abramovich has already freed up funds that have allowed deals for Hakim Ziyech and Timo Werner to be put in place.
They are considered to be exciting additions to a promising young squad at Stamford Bridge, but more arrivals are expected.
Frank Lampard is looking to wrap up a top-four finish that will make it easier for him to add, with Champions League football holding obvious appeal to ambitious performers.
Sutton hopes more money will be made available in west London, with Chelsea still having a number of issues to address - starting between the sticks and the most expensive goalkeeper in world football.
The ex-Blues frontman told Stadium Astro : "What's been the positives for Chelsea this season?
"The likes of [Mason] Mount coming to the fore, Tammy Abraham coming to the fore, they've now done some good business with Ziyech and Werner, so things are looking up.
"But they need to do some more business as well.
"I think the goalkeeper is a massive issue and defensively they've conceded too many goals.
"Frank will know that but there's no point worrying about that at this moment in time.
"Get over the line, get a Champions League spot, you know the riches which come from the Champions League and the finance which comes with that, and then he can address all these issues once the season finishes."
Sutton is not the only former Chelsea star to have pointed out that Lampard still has much work to do in order to turn the Blues into serious contenders for the very biggest prizes available.
Ex-midfielder Craig Burley has also called for more work to be done on the recruitment front over the coming weeks.
He has told ESPN FC : "What they've done is they've gone out and bought attacking players so far.
"But I think we can see the centre-half position and certainly the left-back position needs addressing.
"Although [Marcos] Alonso does some good things going forward, he has generally operated better as a wing-back.
"So I think there are some huge concerns there in that position, as well as the goalkeeper who clearly was untested [in a 1-0 win over Norwich] but there has been animosity between the goalkeeper and the coaching staff, we know that from the last six months or so."