Penna is a talented leg-spinner who took 10 wickets as a replacement player for the Melbourne Stars last season.
The 20-year-old had the lowest average for the Stars, and the best individual bowling performance with 4/20 off her four overs.
Penna made her debut for the ACT Meteors against Meg Lanning’s Victoria last season at the age of 19, after overcoming a knee condition - osteochondritis dissecans – she has had since she was nine.
She was the best bowler that day in a Meteors win, with 1/24 from seven overs at 3.43, including a crucial wicket-maiden over.
Mack is an impressive top-to-middle-order batter who has played 69 Big Bash matches, with 902 runs, having been involved in the competition since its inception.
She is an energetic asset in the field, with five catches last season, including a spectacular snare right on the long-on boundary to dismiss the dangerous Nicola Carey in the Strikers’ comeback win against the Hobart Hurricanes.
The 27-year-old finished with a high score of 18* and five not outs in WBBL|05, testament to a firing Strikers top-order.
Mack was named player of the match for her 72 (97) in a thrilling two-wicket win against eventual champions Western Australia, in last season’s Women’s National Cricket League.
Strikers Head Coach Luke Williams said:
“We were really impressed with Madeline last year who came in as a replacement player for the Stars.
“She took some really handy wickets for them and impressed with her all-round skills, and she will certainly add spin bowling depth and play an important role in our squad.
“Katie certainly was an important member of last year’s side that made the final and we’re really looking forward to seeing what she can bring this season for us.
“Katie is a live wire in the field and her running between the wickets is a big asset to the team, and we’re thrilled to welcome her back.”
The Strikers have one remaining spot on their roster for WBBL|06.
Strikers squad to date: Suzie Bates (c) (NZ), Megan Schutt (Aus), Tahlia McGrath (Aus), Laura Wolvaardt (SA), Darcie Brown, Sarah Coyte, Ellie Falconer, Katie Mack, Tegan McPharlin, Annie O’Neil, Bridget Patterson, Madeline Penna, Alex Price, Amanda-Jade Wellington.