"Obviously Scott Styris played a big role for us in the middle-order, and we were looking at a way to keep our side as strong as possible," Titans coach Matthew Maynard said on Saturday.
"I spoke to Herschelle prior to the tournament, but he was obviously recovering from his hamstring (injury) at that stage. Then I spoke to him again this week and he said yes.
"I worked with Herschelle at Glamorgan, and I thoroughly enjoyed what he brought to the table in terms of his knowledge of the game, his skill with the bat and his ability in the field.
"So it's great to have him on board."
The Titans booked their place in Wednesday's qualifier at Buffalo Park against the Warriors courtesy of four successive wins down the closing stretch, and will go into the decider full of confidence.
Styris was instrumental in their success but the former New Zealand batsman is no longer available for the competition.
Gibbs boasts a wealth of T20 experience, having completed 162 matches at top-class level, and he has appeared in competitions such as the Friends Life T20, the Champions League T20 and Australia's Big Bash.
He has amassed 28 fifties and a century in that time, and, with a strike rate of 125, he poses a potentially lethal threat to the opposition.
"Everything he does is 100 miles per hour," Maynard said.
"He's got loads of energy and is obviously still a top fielder too. He moves like a 20-year-old, not a man who is in his late thirties.
"He reminds me a lot of Viv Richards in that sense. The impact he can have on the dressing room is also a factor as well, because he's an incredibly positive person, and I believe a great signing for us at this stage of the competition."
Gibbs has not played competitive cricket since his last outing for the Perth Scorchers on January 16, and some inconsistent performances in the Big Bash might suggest he was something of a wild card at such a crucial stage of the competition.
However, Maynard was not concerned over issues of form, and believed the 39-year-old brought more to the table than just runs.
"His form doesn't concern me at all. When you are a player like Herschelle, you've probably hit 70 000 balls in your career. So the fact that he hasn't played in a couple of months doesn't concern me. He won't have much to think about, just a see-it-and-hit-it philosophy."
Maynard said he signed Gibbs because of his energy in the field, his impact on the dressing room and his ability with the bat.
The winner of the qualifier will also earn a place in the lucrative Champions League later this year.
The Titans coach believed his team would keep their nerves in check, and he was looking for his charges to make a good start when the game got underway.
"I'm sure there'll be some nerves around on Tuesday morning when we arrive for the match, but we've got a group who really know their games.
"We know that if we play to our potential, it'll be a very close game down there in East London. I believe whichever side starts the game best will have a great chance of coming out on top." – Sapa