Bamford had not featured for the first team since August and his 66th minute strike was his first league goal since his summer move from Middlesbrough.
“He can be very important (for us),” said Bielsa after Leeds’ fifth successive win over their relegation-haunted hosts.
“For him, it is very good for his confidence. He has worked very hard to gain his full fitness.
“And it’s important to have two important strikers in our team.
“It is very difficult to play in an offensive position for any team. And to have different possibilities.
“But we also have Jack Clarke, Jack Harrison, Tyler Roberts and Bamford in offensive positions.
“I always have the idea of having 18 starters in the team and also to have some youngsters to cover the necessities.”
Leeds were not at their best and Bielsa agreed: “It was hard win but a deserved one.
“We had the possession but we didn’t have the chances to score.
“With that possession we might have thought we would have created more chances but it wasn’t the case.”
Bielsa moved to explain Samu Saiz’s absence from the squad with LaLiga outfit Getafe apparently poised to land the playmaker on loan.
“He has a personal situation to solve and the club allowed him to be absent,” said the Leeds chief.
“But I can’t tell you what will happen. What I can tell you he has the permission of the club to be absent but I don’t know what the personal reasons are for his absence.
“It is a decision between the club and Saiz. And I don’t know the facts,” added Bielsa on the former Real Madrid youth player.
“But he has the permission of the club to be absent from the group.
“What will happen in the future is linked to the club and Samu Saiz. As I don’t have information I can’t say anything more.
“It is very complicated to talk about the hypothesis,” he replied when asked if Saiz would be replaced in January if he does leave.
“Because we don’t imagine the situation we can only analyse it if it actually happens. I can’t answer on hypotheticals.”
Asked why he was unaware of the personal reasons Bielsa said: “As it is not a football problem and my job is the football. I have to explain things when it is linked to my zone of work.
“So, this situation has to be explained by the club and Saiz.”
Bolton manager Phil Parkinson was disappointed with the result and the lack of a late penalty for a possible foul on Craig Noone.
But he insisted: “The lads gave absolutely everything. I feel for them and they left nothing in the pitch at all.
“Leeds are a good side but we pressed them terrifically well.
“We restricted them to very few chances. We just lacked when we closed them down and nicked the ball off them that bit of quality to find that pass to go and hurt them.
“We needed to have that bit of calmness when we had the ball. But I can’t fault the lads in terms of effort and commitment.
“They are like me, they are disappointed the ref has decided not to give another stonewall penalty.
“When you are on a difficult run like we have been you need the referee to make big decisions.
“I am sure you have all seen it from the stand but when you see it on the TV monitor you realise we are unfortunate not to be talking about a 1-1 draw.
“Noone nicked the ball on the blind side of the defender and the lad saw him coming and he has just caught him.
“But the difference can sometimes be a £7million player coming off the bench producing one moment of quality - that’s the difference sometimes. That bit of quality can separate the two teams.”