Celtic have brought left-back Kieran Tierney back to the club after his Arsenal contract expired, while recently capped Scotland goalkeeper Ross Doohan and forward Callum Osmand have also signed on free deals.
Hayato Inamura and Shin Yamada have arrived from the J-League, with Benjamin Nygren making it six incomings overall.
However, even before the heavy loss against Ajax, Rodgers stressed the need for further transfers, particularly in forward areas.
“I think we still have some work to do,” he said. “I think the players that we have in the building have been very, very good in pre-season so far but, like I say, we have still work to do in the market.
“I think it’s very clear where our gaps are – in our frontline, where we need support and I’m very confident that we’ll be able to do that before the market finishes.”
Kyogo Furuhashi’s goals were never truly replaced when he left for Rennes in January and with Nicolas Kuhn departing to Serie A side Como, further goals and assists have been taken out of Rodgers’ forward line.
Kyogo scored 85 goals in 165 Celtic appearances, while Kuhn contributed 21 goals and 15 assists last season alone.
Portuguese winger Jota is out with a long-term injury and there are doubts over whether Adam Idah has the attributes to lead the line in high-stakes matches.
Rodgers has consistently said over the past 18 months or so he doesn’t want squad fillers, he wants players that raise the ceiling of his squad.
The Celtic boss insists he is “very confident” of quality coming through the door, but it remains to be seen who those players will be.
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