Buttler slammed 89 off 56 balls in RR's total of 188/6 against GT.
However, Buttler’s half-century went in vain as GT chased down RR’s stiff target of 189 with seven in hand and three balls to spare to book their place in the final.
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It was a scratchy knock from Buttler as he struggled to time the ball initially and was on 39 off 38 balls at one stage. However, the right-hander shifted gears and slammed his next 50 runs in just 18 balls to propel RR to 188/6 in 20 overs.
"I was determined to hang in there. It was a big game for us and we wanted to make sure to put a big score," Buttler said at the post-match press conference.
"Sometimes you got to swallow your ego, if you are finding it hard, you are finding it hard. I don't try to force too much, don't panic.
"The opposition would prefer me to panic and get out, just try to hang in there. I knew at some point I would get away. I trusted myself. Today, it came late in the innings," he added.
The luck was also on Buttler’s side as he got a couple of reprieves during his knock, which took him past 700 runs in the ongoing IPL season.
It was Sanju Samson who got RR off to a scintillating start with his 26-ball 47 and Buttler said the Royals skipper took some pressure off him.
"Yes I was finding it tough to start with and then Sanju came in and played well from ball one. He took a lot of pressure off me. I wouldn't say it was my most fluent innings but I just tried to hang in there and managed to get a little bit away in the end."
For the Titans, David Miller (68* off 38 balls) and Hardik Pandya (40* off 27 balls) starred in the chase as they were involved in an unbroken 106-run partnership.
"We just could not break that partnership, if we managed to take a wicket and found a way to break that partnership, it would have been crucial for us. The deeper they took, the harder it became for us,” Buttler said.
"But we are still alive in the tournament after finishing in the top-two, we still got a chance. We're disappointed today, but still in the tournament," he further stated.
RR will now take on the winner of Eliminator between RCB and LSG in Qualifier 2 on May 27.
(With PTI inputs)