"When Pedro and Eden came on, they gave us an extra gear", Zola said.
Chelsea will look to cement their position in the top four when they take on Leicester City at Stamford Bridge on Saturday afternoon.
Eden Hazard has told Maurizio Sarri he is happy to continue at centre forward as Chelsea continue the search for alternatives up front.
Buck also insisted that "what other clubs may deem acceptable from their supporters in the way of personal identification does not alter our position of zero tolerance" - a thinly-veiled reference to Spurs fans' continued use of a derogatory Jewish term in their own songs.
Zola was voted the best player in Chelsea's history in 2003 after serving the club with distinction as a gifted playmaker with similar skills to Hazard.
Having laboured in their 3-2 win over Derby County in the previous round, Chelsea found Bournemouth in resolute form at Stamford Bridge before substitute Hazard's 84th-minute victor.
Chelsea return to Premier League action against Leicester this weekend, having successfully booked their spot in the Carabao Cup semi-finals on Wednesday.
United States charges Chinese nationals with computer hacking of Navy, NASA
Thursday's announcement was the latest in a series of Justice Department indictments targeting cyberespionage from Beijing . Officials here in Australia and in the U.S. say the theft would've given the Chinese a commercial advantage.
'At the moment, the solution is good, I think, because we played a very good match against Manchester City and against Brighton we were very unsafe for 60 minutes.
"I don't think it makes too much difference being away in the first leg".
Barkley is under no illusions that it will be a hard test for his Chelsea team-mates, especially considering their 3-1 Premier League defeat to Mauricio Pochettino's side at Wembley in November.
"There are a lot of proud players in our team".
Chelsea assistant manager Gianfranco Zola has urged Eden Hazard to reject a potential offer from Real Madrid and focus on becoming the Blues' all-time greatest player.
Should Drinkwater leave Chelsea for more first team opportunities?