Antrim snatched a dramatic 3-20 to 2-22 extra-time victory over Carlow in their Christy Ring Cup opener as Down beat Roscommon 2-24 to 1-20 at Ballycran.
Neil McManus hit 1-13 for the Saffrons as they fought back from seven down in the first half and four in arrears late in normal time to force extra-time.
Niall McKenna and Ciaran Clarke notched Antrim's goals as the scoreline was 2-16 to 2-16 at the end of normal time.
Carlow moved four up again before McManus' goal spurred Antrim again.
The McManus goal brought the sides level with four minutes of extra-time remaining and while Carlow edged one ahead again, late points from McManus and James McNaughton secured Antrim's victory.
Denis Murphy hit 16 of Carlow's points with Martin Kavanagh notching both of the home team's goals.
Carlow led 1-6 to 0-2 after 18 minutes and remained six clear in first-half injury-time before McKenna's goal gave Antrim a huge boost.
The Barrowsiders extended their advantage to 1-10 to 1-5 after 39 minutes and remained 1-15 to 1-11 ahead with nine minutes of normal time left.
Clarke's goal cut Carlow's lead to a point but the home team responded with three straight scores to lead by four with five minutes left.
However, three more McManus points and a Paul Shiels score enabled the Saffrons to force extra-time.
At Ballycran, Roscommon led 0-9 to 0-6 after 15 minutes when Malachy Magee's goal brought the sides level.
The Rossies regrouped to lead 1-13 to 1-10 at half-time and extended that to 1-16 to 1-11 before Gareth Johnston's introduction help spur a Down comeback.
Eoghan Sands' 58th-minute goal moved Down ahead as they pulled clear.
The Mourne County's win was a morale booster for Marty Mallon's side after their surprise Ulster semi-final defeat by Armagh a fortnight ago.
The victories means the two Ulster counties will be in the winners' section of the competition but Carlow and Roscommon are not yet out of the competition.
Rackard and Meagher Cup round-ups
Goals from Damien Casey and Sean Og Grogan helped Tyrone edge out Monaghan 2-11 to 0-16 in the Nicky Rackard Cup at Castleblayney.
Derry withstood a strong Louth comeback to take a 2-17 to 1-12 win in Dowdallshill with Meehaul McGrath and Ruairi Convery netting for the Oak Leafers.
Davin Flynn scored 1-5 from play in Donegal's 1-19 to 0-13 win over beaten Ulster finalists Armagh in Letterkenny.
Cavan returned to the Lory Meagher Cup for the first time in six years, but failed to lead as Warwickshire claimed a 3-28 to 1-14 win with former Antrim star Liam Watson netted two of the Exiles' goals.
Sean Corrigan fired 3-8 including the winning point for Fermanagh in their 5-13 to 2-21 win over Leitrim.
Antrim (v Carlow): C O'Connell; S McCrory, J Dillon, S Rooney; P Burke, M Donnelly, C Johnston; C McKinley, P Shiels; M Connolly, C McCann, E Campbell; C Johnston, N McManus, C Clarke.
Carlow (v Antrim): J Carroll; A Corcoran, P Doyle, G Bennett; D Byrne, D English, R Coady; E Redmond, J Doyle; JM Nolan, M Kavanagh, K McDonald; D Murphy, P Coady, S Murphy.
Christy Ring Cup
Mayo 0-16 0-17 Kildare
Carlow 2-22 3-20 Antrim - aet
Down 2-24 1-20 Roscommon
Nicky Rackard Cup
Louth 1-12 2-17 Derry
Monaghan 0-16 2-11 Tyrone
Donegal 1-19 0-13 Armagh
Lory Meagher Cup
Fermanagh 5-13 2-21 Leitrim
Cavan 1-14 3-28 Warwickshire
Sligo 4-14 0-17 Lancashire
Allianz Hurling League Division One Final
Tipperary 0-14 3-21 Galway
Leinster SHC round 1
Meath 3-20 2-17 Kerry
Laois 1-23 2-17 Westmeath
Christy Ring Cup
Wicklow 0-17 0-16 London