Leinster go in at the break in Dublin with a four-point lead after a back-and-forth first half.
Two penalties from Lions gave the visitors a lead, but Leo Cullen's men battled back with a try from Josh van der Flier to give his side a narrow advantage at the break.
The South African side are certainly giving Leinster a good game and an interesting second half is in store.
Leinster's momentum is lost after a spilled ball is hacked downfield by the Lions, who attempt to pin Leinster back with a kick to the corner but James Lowe is well positioned to deal with it.
ThomasHughes 20', substituted for Hughes at 20 minutesThomas 25', substituted for Thomas at 25 minutesJennings 59', substituted for Jennings at 59 minutes
Number
11
11, Stephens
Stephens
Number
10
10, Sheedy
Sheedy
Number
9
9, Davies
Davies
Number
1
1, E Byrne
E ByrneDomachowski 51', substituted for Domachowski at 51 minutes
Number
2
2, E Lloyd
E Lloyd12', Yellow card at 12 minutesHughes 47', substituted for Hughes at 47 minutes
Number
3
3, Assiratti
AssirattiLitterick 49', substituted for Litterick at 49 minutes
Number
4
4, McNally
McNally
Number
5
5, EI Williams
EI WilliamsThornton 69', substituted for Thornton at 69 minutes
Number
6
6, Donnell
DonnellBotham 47', substituted for Botham at 47 minutes
Number
7
7, Thomas
ThomasYoung 47', substituted for Young at 47 minutes
Number
8
8, Lawrence
Lawrence
Substitutes
home team, Cardiff Rugby
Number
16
16, Hughes
Hughes
Number
17
17, Domachowski
Domachowski
Number
18
18, Litterick
Litterick
Number
19
19, Thornton
Thornton
Number
20
20, Botham
Botham
Number
21
21, Young
Young
Number
22
22, Mulder
Mulder
Number
23
23, Jennings
Jennings
away team, Ulster
Starting lineup
Number
15
15, McIlroy
McIlroy
Number
14
14, Kok
Kok
Number
13
13, Postlethwaite
Postlethwaite
Number
12
12, McCloskey
McCloskeyCarson 66', substituted for Carson at 66 minutes
Number
11
11, Lowry
Lowry
Number
10
10, Morgan
MorganCooney 69', substituted for Cooney at 69 minutes
Number
9
9, Doak
Doak
Number
1
1, O'Sullivan
O'SullivanWarwick 59', substituted for Warwick at 59 minutes
Number
2
2, McCormick
McCormickAndrew 78', substituted for Andrew at 78 minutes
Number
3
3, O'Toole
O'TooleWilson 52', substituted for Wilson at 52 minutes
Number
4
4, Henderson
HendersonSheridan 25', substituted for Sheridan at 25 minutesRea 70', substituted for Rea at 70 minutes
ThomasHughes 20', substituted for Hughes at 20 minutesThomas 25', substituted for Thomas at 25 minutesJennings 59', substituted for Jennings at 59 minutes
Number
11
11, Stephens
Stephens
Number
10
10, Sheedy
Sheedy
Number
9
9, Davies
Davies
Number
1
1, E Byrne
E ByrneDomachowski 51', substituted for Domachowski at 51 minutes
Number
2
2, E Lloyd
E Lloyd12', Yellow card at 12 minutesHughes 47', substituted for Hughes at 47 minutes
Number
3
3, Assiratti
AssirattiLitterick 49', substituted for Litterick at 49 minutes
Number
4
4, McNally
McNally
Number
5
5, EI Williams
EI WilliamsThornton 69', substituted for Thornton at 69 minutes
Number
6
6, Donnell
DonnellBotham 47', substituted for Botham at 47 minutes
Number
7
7, Thomas
ThomasYoung 47', substituted for Young at 47 minutes
Number
8
8, Lawrence
Lawrence
Substitutes
Number
16
16, Hughes
Hughes
Number
17
17, Domachowski
Domachowski
Number
18
18, Litterick
Litterick
Number
19
19, Thornton
Thornton
Number
20
20, Botham
Botham
Number
21
21, Young
Young
Number
22
22, Mulder
Mulder
Number
23
23, Jennings
Jennings
away team, Ulster
Starting lineup
Number
15
15, McIlroy
McIlroy
Number
14
14, Kok
Kok
Number
13
13, Postlethwaite
Postlethwaite
Number
12
12, McCloskey
McCloskeyCarson 66', substituted for Carson at 66 minutes
Number
11
11, Lowry
Lowry
Number
10
10, Morgan
MorganCooney 69', substituted for Cooney at 69 minutes
Number
9
9, Doak
Doak
Number
1
1, O'Sullivan
O'SullivanWarwick 59', substituted for Warwick at 59 minutes
Number
2
2, McCormick
McCormickAndrew 78', substituted for Andrew at 78 minutes
Number
3
3, O'Toole
O'TooleWilson 52', substituted for Wilson at 52 minutes
Number
4
4, Henderson
HendersonSheridan 25', substituted for Sheridan at 25 minutesRea 70', substituted for Rea at 70 minutes