The Chiefs have made their first signing from outside of their current squad for next season, recruiting former Crusaders hooker Quentin MacDonald.
The back-to-back champions have also secured the services of Waikato halfback and captain Brad Weber for next season, who was part of the wider training group this year.
Tasman's MacDonald has returned to New Zealand after playing for Munster in Ireland and will join the Chiefs after this year's national provincial premiership season - keen to make his return to Super Rugby after playing 22 times for the Crusaders from 2010-12 and six caps for the Blues last year.
''It is a fantastic opportunity with an awesome coaching staff and a great player base,'' MacDonald, 25, said.
With a question mark over the career of Chiefs hooker Hika Elliot, who was invalided out of this season with a serious neck injury, and doubts over the future of 36-year-old Mahonri Schwalger, there is a big opportunity for MacDonald to make his mark in competition with young rakes Nathan Harris and Rhys Marshall.
Weber, 23, was originally part of the Chiefs wider training squad this season.
He has played seven matches for the Chiefs, having made his debut against the Crusaders in the opening round this year.
''I feel this is the best place for my development,'' said Weber. ''I have come a long way in a year and the coaching at the Chiefs is unreal. I enjoy the company of the boys and love the culture here.''
Chiefs head coach Dave Rennie expressed satisfaction at the latest signings.
''Brad has had a strong debut season and provides a genuine point of difference to our other halfbacks,'' Rennie said.
''He's a top man and we're rapt he's on board for 2015. Tom, Straws and I have all coached Quentin at national age grade level. His athleticism, his skill set and experience will be invaluable to our squad,'' he said.
MacDonald has played more than 50 matches for the Tasman Makos and represented New Zealand Under-20 and the Maori All Blacks.
Weber is also a former New Zealand U-20 player and started his ITM Cup career with Otago before moving to Waikato last year.
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