Leicester made it four straight European Challenge Cup wins after they held out to defeat Calvisano 20-13.
Teenager Freddie Steward had given a much-changed Leicester side a flying start in their Pool 5 match at Pata Stadium with a try in the opening minute before the Italians, thrashed 59-7 a week earlier, responded through a penalty from Paolo Pescetto to trail 8-3 at the break.
But, after Tigers prop Greg Bateman had been sin-binned, Calvisano had lock Davide Zanetti shown a red card on the hour following an incident at the ruck. Andy Forsyth then crossed before Nephi Leatigaga's late try made sure of the win, with Calvisano gaining a bonus-point score through Anibal Panceyra-Garrido late on.
Pau made the most of their rescheduled match against Cardiff Blues to win 34-29 at the Stade du Hameau after Friday's fixture had been put back on health and safety grounds following persistent, heavy rain.
After going behind early on, the hosts made up for lost time with three first-half tries to lead 24-7.
Although the Welsh side fought back as Owen Lane completed a hat-trick, it was not enough - but at least the bonus points keep alive some hope of progress.
In Pool 4, leaders Bristol Bears scored a late try through Harry Thacker to complete a fightback and win 18-16 at Stade Francais.
The hosts had been 10-8 in front at the break after Nicolas Sanchez's penalty added to a converted try from Waisea Nayacalev.
The bears kept themselves in touch through the boot of Callum Sheedy, with Thacker's converted score following a rolling maul after 77 minutes proving crucial.
Edinburgh boosted their qualification chances for the knockout stage with a 9-7 win at Wasps following Jaco Van Der Walt's late penalty.
The Scottish side are now one point behind Pool 3 leaders Bordeaux, who beat Agen 33-6, ahead of their round five showdown at Stade Chaban-Delmas.
Nizaam Carr's converted try had seen the English side ahead 7-3 at the break, but Edinburgh capitalised on a yellow card for Josh Bassett as South African Van Der Walt held his nerve with two decisive kicks to seal a hard-earned win, which finished Wasps' slim chances of progress.
Saturday's late match in Pool 2 saw Scarlets run in six tries to sweep aside Bayonne 46-5 in testing conditions at Llanelli.
Full-back Leigh Halfpenny added two penalties to his successful conversions - which included from his own late try for a match tally of 21 points.
The comfortable win puts the Welsh club four points behind leaders Toulon, who had earlier won 26-20 at London Irish - a result which all but ended the home side's hopes of qualifying as one of the best runners-up.
Following a try from Irish number eight Albert Tuisue, the French side made the most of some poor discipline as Anthony Belleau kicked four penalties.
London Irish captain Ruan Botha and Terrence Heptema were both sent to the sin-bin during the first half.