Marc Guiu netted an incredible first half hat-trick as Chelsea came away from Stamford Bridge with their 100 percent record in the Conference League intact.
The Blues went into Thursday's match top of the tournament's league phase, with Enzo Maresca's side having won all of their matches since losing to Servette in the play-off second leg.
Maresca handed starts to Cobham academy graduates Tyrique George and Josh Acheampong, with the former signing a contract extension this week.
The pair impressed once again, but it was 18-year-old summer signing Guiu who stole the headlines at Stamford Bridge, adding to his two goals in the Conference League this season.
The Spaniard, who scored twice against Astana last time out, netted an incredible first half perfect hat-trick in an impressive performance leading the line for Chelsea.
Kiernan Dewsbury-Hall also netted in the first half, with Chelsea adding the goals in the second half by blah blah and blah.
Guiu scored a first half hat-trick against Astana.
Guiu scored a first half hat-trick against Astana. / IMAGO / Pro Sports Images
It was the perfect start for Maresca's men as Guiu seized on a mistake by the Shamrock Rovers defence, with a pass back to Leon Pohls intercepted by Guiu, who headed in after 22 minutes.
Despite the dominant start, the visitors hit back just four minutes later as Markus Poom netted after a Shamrock corner, firing past Filip Jorgensen against the run of play.
Guiu was able to capitalise on another mistake by the Irish side on the 34th minute, rounding the goalkeeper before slotting a left-footed strike into the net from a tight angle.
Dewsbury-Hall added a third for Chelsea five minutes later, with a tackle on Christopher Nkunku seeing the ball fall to the midfielder on the right side of Shamrock's box before he fired a low left-footed shot past Pohls.
While Chelsea would have been forgiven for taking their foot off the gas for the remainder of the first half, Maresca's men were keen to impress and kept pressing with intensity before netting a fourth.
A short Blues corner eventually saw Noni Madueke pick out Guiu with a sublime cross before the striker headed in to secure a perfect hat-trick before half-time.
Marc Cucurella scored in consecutive games with a fine strike against Shamrock Rovers.
Marc Cucurella scored in consecutive games with a fine strike against Shamrock Rovers. / IMAGO / Pro Sports Images
It was more of the same in the second half for Chelsea, with Marc Cucurella arriving late before being picked out by Nkunku before slotting home to make it two goals in two games.
Maresca used the second half to blood several youth players, with Harvey Vale and Harrison Murray-Campbell getting the opportunity to impress at Stamford Bridge.
Shamrock Rovers thought they should have had a penalty when Murray-Campbell brought down one of the visitor's attackers, but the referee waved the complaints away.
Joao Felix also made his return to action, coming off the bench, and looked lively in the number 10 role as Chelsea dominated towards the end of the match but were unable to add to their lead.
The Blues have already qualified for the next round of the tournament and will now turn their attention to their trip to Goodison Park as they prepare to face Everton on Sunday in a clash that could see them go top of the Premier League.